diff --git a/ds3/ds3Client_test.go b/ds3/ds3Client_test.go
index 3fbe512..34c8492 100644
--- a/ds3/ds3Client_test.go
+++ b/ds3/ds3Client_test.go
@@ -1916,11 +1916,11 @@ func TestVerifyPhysicalPlacementForObjectsWithFullDetailsSpectraS3(t *testing.T)
     ds3Testing.AssertStringPtrIsNil(t, "PartiallyVerifiedEndOfTape", tape.PartiallyVerifiedEndOfTape)
     ds3Testing.AssertNonNilStringPtr(t, "PartitionId", "dc681797-927a-4eb0-9652-d19d06534e50", tape.PartitionId)
     if tape.PreviousState != nil {
-        t.Fatalf("Expeted previous state to be 'nil' but was '%s'.", tape.PreviousState.String())
+        t.Fatalf("Expeted previous state to be 'nil' but was '%v'.", tape.PreviousState)
     }
     ds3Testing.AssertStringPtrIsNil(t, "SerialNumber", tape.SerialNumber)
     if tape.State != models.TAPE_STATE_PENDING_INSPECTION {
-        t.Fatalf("Expected tape state 'TAPE_STATE_PENDING_INSPECTION' but got '%s'.", tape.State.String())
+        t.Fatalf("Expected tape state 'TAPE_STATE_PENDING_INSPECTION' but got '%v'.", tape.State)
     }
     ds3Testing.AssertStringPtrIsNil(t, "StorageDomainId", tape.StorageDomainMemberId)
     ds3Testing.AssertBool(t, "TakeOwnershipPending", false, tape.TakeOwnershipPending)
diff --git a/ds3/models/responseModels.go b/ds3/models/responseModels.go
index 433058f..45ca227 100644
--- a/ds3/models/responseModels.go
+++ b/ds3/models/responseModels.go
@@ -89,6 +89,16 @@ func (autoInspectMode AutoInspectMode) StringPtr() *string {
     result := autoInspectMode.String()
     return &result
 }
+
+func newAutoInspectModeFromContent(content []byte, aggErr *AggregateError) *AutoInspectMode {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(AutoInspectMode)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type AzureDataReplicationRule struct {
     DataPolicyId string
     Id string
@@ -143,7 +153,7 @@ func (blob *Blob) parse(xmlNode *XmlNode, aggErr *AggregateError) {
         case "Checksum":
             blob.Checksum = parseNullableString(child.Content)
         case "ChecksumType":
-            parseNullableEnum(child.Content, blob.ChecksumType, aggErr)
+            blob.ChecksumType = newChecksumTypeFromContent(child.Content, aggErr)
         case "Id":
             blob.Id = parseString(child.Content)
         case "Length":
@@ -205,6 +215,16 @@ func (priority Priority) StringPtr() *string {
     result := priority.String()
     return &result
 }
+
+func newPriorityFromContent(content []byte, aggErr *AggregateError) *Priority {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(Priority)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type Bucket struct {
     CreationDate string
     DataPolicyId string
@@ -321,6 +341,16 @@ func (bucketAclPermission BucketAclPermission) StringPtr() *string {
     result := bucketAclPermission.String()
     return &result
 }
+
+func newBucketAclPermissionFromContent(content []byte, aggErr *AggregateError) *BucketAclPermission {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(BucketAclPermission)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type CanceledJob struct {
     BucketId string
     CachedSizeInBytes int64
@@ -505,6 +535,16 @@ func (dataIsolationLevel DataIsolationLevel) StringPtr() *string {
     result := dataIsolationLevel.String()
     return &result
 }
+
+func newDataIsolationLevelFromContent(content []byte, aggErr *AggregateError) *DataIsolationLevel {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(DataIsolationLevel)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type DataPathBackend struct {
     Activated bool
     AllowNewJobRequests bool
@@ -539,7 +579,7 @@ func (dataPathBackend *DataPathBackend) parse(xmlNode *XmlNode, aggErr *Aggregat
         case "CacheAvailableRetryAfterInSeconds":
             dataPathBackend.CacheAvailableRetryAfterInSeconds = parseInt(child.Content, aggErr)
         case "DefaultVerifyDataAfterImport":
-            parseNullableEnum(child.Content, dataPathBackend.DefaultVerifyDataAfterImport, aggErr)
+            dataPathBackend.DefaultVerifyDataAfterImport = newPriorityFromContent(child.Content, aggErr)
         case "DefaultVerifyDataPriorToImport":
             dataPathBackend.DefaultVerifyDataPriorToImport = parseBool(child.Content, aggErr)
         case "Id":
@@ -639,6 +679,16 @@ func (dataPersistenceRuleType DataPersistenceRuleType) StringPtr() *string {
     result := dataPersistenceRuleType.String()
     return &result
 }
+
+func newDataPersistenceRuleTypeFromContent(content []byte, aggErr *AggregateError) *DataPersistenceRuleType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(DataPersistenceRuleType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type DataPlacementRuleState Enum
 
 const (
@@ -676,6 +726,16 @@ func (dataPlacementRuleState DataPlacementRuleState) StringPtr() *string {
     result := dataPlacementRuleState.String()
     return &result
 }
+
+func newDataPlacementRuleStateFromContent(content []byte, aggErr *AggregateError) *DataPlacementRuleState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(DataPlacementRuleState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type DataPolicy struct {
     AlwaysForcePutJobCreation bool
     AlwaysMinimizeSpanningAcrossMedia bool
@@ -801,6 +861,16 @@ func (dataReplicationRuleType DataReplicationRuleType) StringPtr() *string {
     result := dataReplicationRuleType.String()
     return &result
 }
+
+func newDataReplicationRuleTypeFromContent(content []byte, aggErr *AggregateError) *DataReplicationRuleType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(DataReplicationRuleType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type DegradedBlob struct {
     AzureReplicationRuleId *string
     BlobId string
@@ -940,6 +1010,16 @@ func (featureKeyType FeatureKeyType) StringPtr() *string {
     result := featureKeyType.String()
     return &result
 }
+
+func newFeatureKeyTypeFromContent(content []byte, aggErr *AggregateError) *FeatureKeyType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(FeatureKeyType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type Group struct {
     BuiltIn bool
     Id string
@@ -1162,6 +1242,16 @@ func (jobChunkBlobStoreState JobChunkBlobStoreState) StringPtr() *string {
     result := jobChunkBlobStoreState.String()
     return &result
 }
+
+func newJobChunkBlobStoreStateFromContent(content []byte, aggErr *AggregateError) *JobChunkBlobStoreState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(JobChunkBlobStoreState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type JobChunkClientProcessingOrderGuarantee Enum
 
 const (
@@ -1199,6 +1289,16 @@ func (jobChunkClientProcessingOrderGuarantee JobChunkClientProcessingOrderGuaran
     result := jobChunkClientProcessingOrderGuarantee.String()
     return &result
 }
+
+func newJobChunkClientProcessingOrderGuaranteeFromContent(content []byte, aggErr *AggregateError) *JobChunkClientProcessingOrderGuarantee {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(JobChunkClientProcessingOrderGuarantee)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type JobRequestType Enum
 
 const (
@@ -1239,6 +1339,16 @@ func (jobRequestType JobRequestType) StringPtr() *string {
     result := jobRequestType.String()
     return &result
 }
+
+func newJobRequestTypeFromContent(content []byte, aggErr *AggregateError) *JobRequestType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(JobRequestType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type JobRestore Enum
 
 const (
@@ -1279,6 +1389,16 @@ func (jobRestore JobRestore) StringPtr() *string {
     result := jobRestore.String()
     return &result
 }
+
+func newJobRestoreFromContent(content []byte, aggErr *AggregateError) *JobRestore {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(JobRestore)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type LtfsFileNamingMode Enum
 
 const (
@@ -1316,6 +1436,16 @@ func (ltfsFileNamingMode LtfsFileNamingMode) StringPtr() *string {
     result := ltfsFileNamingMode.String()
     return &result
 }
+
+func newLtfsFileNamingModeFromContent(content []byte, aggErr *AggregateError) *LtfsFileNamingMode {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(LtfsFileNamingMode)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type Node struct {
     DataPathHttpPort *int
     DataPathHttpsPort *int
@@ -1435,6 +1565,16 @@ func (s3InitialDataPlacementPolicy S3InitialDataPlacementPolicy) StringPtr() *st
     result := s3InitialDataPlacementPolicy.String()
     return &result
 }
+
+func newS3InitialDataPlacementPolicyFromContent(content []byte, aggErr *AggregateError) *S3InitialDataPlacementPolicy {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(S3InitialDataPlacementPolicy)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type S3Object struct {
     BucketId string
     CreationDate *string
@@ -1504,6 +1644,16 @@ func (s3ObjectType S3ObjectType) StringPtr() *string {
     result := s3ObjectType.String()
     return &result
 }
+
+func newS3ObjectTypeFromContent(content []byte, aggErr *AggregateError) *S3ObjectType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(S3ObjectType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type S3Region Enum
 
 const (
@@ -1574,6 +1724,16 @@ func (s3Region S3Region) StringPtr() *string {
     result := s3Region.String()
     return &result
 }
+
+func newS3RegionFromContent(content []byte, aggErr *AggregateError) *S3Region {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(S3Region)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type StorageDomain struct {
     AutoEjectMediaFullThreshold *int64
     AutoEjectUponCron *string
@@ -1621,7 +1781,7 @@ func (storageDomain *StorageDomain) parse(xmlNode *XmlNode, aggErr *AggregateErr
         case "SecureMediaAllocation":
             storageDomain.SecureMediaAllocation = parseBool(child.Content, aggErr)
         case "VerifyPriorToAutoEject":
-            parseNullableEnum(child.Content, storageDomain.VerifyPriorToAutoEject, aggErr)
+            storageDomain.VerifyPriorToAutoEject = newPriorityFromContent(child.Content, aggErr)
         case "WriteOptimization":
             parseEnum(child.Content, &storageDomain.WriteOptimization, aggErr)
         default:
@@ -1722,6 +1882,16 @@ func (storageDomainFailureType StorageDomainFailureType) StringPtr() *string {
     result := storageDomainFailureType.String()
     return &result
 }
+
+func newStorageDomainFailureTypeFromContent(content []byte, aggErr *AggregateError) *StorageDomainFailureType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(StorageDomainFailureType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type StorageDomainMember struct {
     AutoCompactionThreshold *int
     Id string
@@ -1797,6 +1967,16 @@ func (storageDomainMemberState StorageDomainMemberState) StringPtr() *string {
     result := storageDomainMemberState.String()
     return &result
 }
+
+func newStorageDomainMemberStateFromContent(content []byte, aggErr *AggregateError) *StorageDomainMemberState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(StorageDomainMemberState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type SystemFailure struct {
     Date string
     ErrorMessage *string
@@ -1872,6 +2052,16 @@ func (systemFailureType SystemFailureType) StringPtr() *string {
     result := systemFailureType.String()
     return &result
 }
+
+func newSystemFailureTypeFromContent(content []byte, aggErr *AggregateError) *SystemFailureType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(SystemFailureType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type UnavailableMediaUsagePolicy Enum
 
 const (
@@ -1912,6 +2102,16 @@ func (unavailableMediaUsagePolicy UnavailableMediaUsagePolicy) StringPtr() *stri
     result := unavailableMediaUsagePolicy.String()
     return &result
 }
+
+func newUnavailableMediaUsagePolicyFromContent(content []byte, aggErr *AggregateError) *UnavailableMediaUsagePolicy {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(UnavailableMediaUsagePolicy)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type SpectraUser struct {
     AuthId *string
     DefaultDataPolicyId *string
@@ -1984,6 +2184,16 @@ func (versioningLevel VersioningLevel) StringPtr() *string {
     result := versioningLevel.String()
     return &result
 }
+
+func newVersioningLevelFromContent(content []byte, aggErr *AggregateError) *VersioningLevel {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(VersioningLevel)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type WriteOptimization Enum
 
 const (
@@ -2021,6 +2231,16 @@ func (writeOptimization WriteOptimization) StringPtr() *string {
     result := writeOptimization.String()
     return &result
 }
+
+func newWriteOptimizationFromContent(content []byte, aggErr *AggregateError) *WriteOptimization {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(WriteOptimization)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type WritePreferenceLevel Enum
 
 const (
@@ -2064,6 +2284,16 @@ func (writePreferenceLevel WritePreferenceLevel) StringPtr() *string {
     result := writePreferenceLevel.String()
     return &result
 }
+
+func newWritePreferenceLevelFromContent(content []byte, aggErr *AggregateError) *WritePreferenceLevel {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(WritePreferenceLevel)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type AzureTargetFailureNotificationRegistration struct {
     CreationDate string
     Format HttpResponseFormatType
@@ -2957,6 +3187,16 @@ func (poolFailureType PoolFailureType) StringPtr() *string {
     result := poolFailureType.String()
     return &result
 }
+
+func newPoolFailureTypeFromContent(content []byte, aggErr *AggregateError) *PoolFailureType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(PoolFailureType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type PoolHealth Enum
 
 const (
@@ -2994,6 +3234,16 @@ func (poolHealth PoolHealth) StringPtr() *string {
     result := poolHealth.String()
     return &result
 }
+
+func newPoolHealthFromContent(content []byte, aggErr *AggregateError) *PoolHealth {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(PoolHealth)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type PoolPartition struct {
     Id string
     Name *string
@@ -3066,6 +3316,16 @@ func (poolState PoolState) StringPtr() *string {
     result := poolState.String()
     return &result
 }
+
+func newPoolStateFromContent(content []byte, aggErr *AggregateError) *PoolState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(PoolState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type PoolType Enum
 
 const (
@@ -3103,6 +3363,16 @@ func (poolType PoolType) StringPtr() *string {
     result := poolType.String()
     return &result
 }
+
+func newPoolTypeFromContent(content []byte, aggErr *AggregateError) *PoolType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(PoolType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type SuspectBlobPool struct {
     BlobId string
     BucketId string
@@ -3175,6 +3445,16 @@ func (quiesced Quiesced) StringPtr() *string {
     result := quiesced.String()
     return &result
 }
+
+func newQuiescedFromContent(content []byte, aggErr *AggregateError) *Quiesced {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(Quiesced)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type ReservedTaskType Enum
 
 const (
@@ -3215,6 +3495,16 @@ func (reservedTaskType ReservedTaskType) StringPtr() *string {
     result := reservedTaskType.String()
     return &result
 }
+
+func newReservedTaskTypeFromContent(content []byte, aggErr *AggregateError) *ReservedTaskType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(ReservedTaskType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type ImportExportConfiguration Enum
 
 const (
@@ -3252,6 +3542,16 @@ func (importExportConfiguration ImportExportConfiguration) StringPtr() *string {
     result := importExportConfiguration.String()
     return &result
 }
+
+func newImportExportConfigurationFromContent(content []byte, aggErr *AggregateError) *ImportExportConfiguration {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(ImportExportConfiguration)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type SuspectBlobTape struct {
     BlobId string
     Id string
@@ -3347,7 +3647,7 @@ func (tape *Tape) parse(xmlNode *XmlNode, aggErr *AggregateError) {
         case "PartitionId":
             tape.PartitionId = parseNullableString(child.Content)
         case "PreviousState":
-            parseNullableEnum(child.Content, tape.PreviousState, aggErr)
+            tape.PreviousState = newTapeStateFromContent(child.Content, aggErr)
         case "SerialNumber":
             tape.SerialNumber = parseNullableString(child.Content)
         case "State":
@@ -3361,7 +3661,7 @@ func (tape *Tape) parse(xmlNode *XmlNode, aggErr *AggregateError) {
         case "Type":
             tape.Type = parseString(child.Content)
         case "VerifyPending":
-            parseNullableEnum(child.Content, tape.VerifyPending, aggErr)
+            tape.VerifyPending = newPriorityFromContent(child.Content, aggErr)
         case "WriteProtected":
             tape.WriteProtected = parseBool(child.Content, aggErr)
         default:
@@ -3507,6 +3807,16 @@ func (tapeDriveState TapeDriveState) StringPtr() *string {
     result := tapeDriveState.String()
     return &result
 }
+
+func newTapeDriveStateFromContent(content []byte, aggErr *AggregateError) *TapeDriveState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(TapeDriveState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type TapeDriveType Enum
 
 const (
@@ -3562,6 +3872,16 @@ func (tapeDriveType TapeDriveType) StringPtr() *string {
     result := tapeDriveType.String()
     return &result
 }
+
+func newTapeDriveTypeFromContent(content []byte, aggErr *AggregateError) *TapeDriveType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(TapeDriveType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type DetailedTapeFailure struct {
     Date string
     ErrorMessage *string
@@ -3688,6 +4008,16 @@ func (tapeFailureType TapeFailureType) StringPtr() *string {
     result := tapeFailureType.String()
     return &result
 }
+
+func newTapeFailureTypeFromContent(content []byte, aggErr *AggregateError) *TapeFailureType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(TapeFailureType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type TapeLibrary struct {
     Id string
     ManagementUrl *string
@@ -3737,7 +4067,7 @@ func (tapePartition *TapePartition) parse(xmlNode *XmlNode, aggErr *AggregateErr
         case "AutoCompactionEnabled":
             tapePartition.AutoCompactionEnabled = parseBool(child.Content, aggErr)
         case "DriveType":
-            parseNullableEnum(child.Content, tapePartition.DriveType, aggErr)
+            tapePartition.DriveType = newTapeDriveTypeFromContent(child.Content, aggErr)
         case "ErrorMessage":
             tapePartition.ErrorMessage = parseNullableString(child.Content)
         case "Id":
@@ -3872,6 +4202,16 @@ func (tapePartitionFailureType TapePartitionFailureType) StringPtr() *string {
     result := tapePartitionFailureType.String()
     return &result
 }
+
+func newTapePartitionFailureTypeFromContent(content []byte, aggErr *AggregateError) *TapePartitionFailureType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(TapePartitionFailureType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type TapePartitionState Enum
 
 const (
@@ -3912,6 +4252,16 @@ func (tapePartitionState TapePartitionState) StringPtr() *string {
     result := tapePartitionState.String()
     return &result
 }
+
+func newTapePartitionStateFromContent(content []byte, aggErr *AggregateError) *TapePartitionState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(TapePartitionState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type TapeState Enum
 
 const (
@@ -4024,6 +4374,16 @@ func (tapeState TapeState) StringPtr() *string {
     result := tapeState.String()
     return &result
 }
+
+func newTapeStateFromContent(content []byte, aggErr *AggregateError) *TapeState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(TapeState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type AzureTarget struct {
     AccountKey *string
     AccountName *string
@@ -4284,6 +4644,16 @@ func (ds3TargetAccessControlReplication Ds3TargetAccessControlReplication) Strin
     result := ds3TargetAccessControlReplication.String()
     return &result
 }
+
+func newDs3TargetAccessControlReplicationFromContent(content []byte, aggErr *AggregateError) *Ds3TargetAccessControlReplication {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(Ds3TargetAccessControlReplication)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type Ds3TargetFailure struct {
     Date string
     ErrorMessage *string
@@ -4406,7 +4776,7 @@ func (s3Target *S3Target) parse(xmlNode *XmlNode, aggErr *AggregateError) {
         case "Quiesced":
             parseEnum(child.Content, &s3Target.Quiesced, aggErr)
         case "Region":
-            parseNullableEnum(child.Content, s3Target.Region, aggErr)
+            s3Target.Region = newS3RegionFromContent(child.Content, aggErr)
         case "SecretKey":
             s3Target.SecretKey = parseNullableString(child.Content)
         case "StagedDataExpirationInDays":
@@ -4639,6 +5009,16 @@ func (targetFailureType TargetFailureType) StringPtr() *string {
     result := targetFailureType.String()
     return &result
 }
+
+func newTargetFailureTypeFromContent(content []byte, aggErr *AggregateError) *TargetFailureType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(TargetFailureType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type TargetReadPreferenceType Enum
 
 const (
@@ -4688,6 +5068,16 @@ func (targetReadPreferenceType TargetReadPreferenceType) StringPtr() *string {
     result := targetReadPreferenceType.String()
     return &result
 }
+
+func newTargetReadPreferenceTypeFromContent(content []byte, aggErr *AggregateError) *TargetReadPreferenceType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(TargetReadPreferenceType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type TargetState Enum
 
 const (
@@ -4725,6 +5115,16 @@ func (targetState TargetState) StringPtr() *string {
     result := targetState.String()
     return &result
 }
+
+func newTargetStateFromContent(content []byte, aggErr *AggregateError) *TargetState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(TargetState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type BulkObject struct {
     Bucket *string
     Id *string
@@ -4913,6 +5313,16 @@ func (blobStoreTaskState BlobStoreTaskState) StringPtr() *string {
     result := blobStoreTaskState.String()
     return &result
 }
+
+func newBlobStoreTaskStateFromContent(content []byte, aggErr *AggregateError) *BlobStoreTaskState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(BlobStoreTaskState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type BlobStoreTasksInformation struct {
     Tasks []BlobStoreTaskInformation
 }
@@ -4991,6 +5401,16 @@ func (cacheEntryState CacheEntryState) StringPtr() *string {
     result := cacheEntryState.String()
     return &result
 }
+
+func newCacheEntryStateFromContent(content []byte, aggErr *AggregateError) *CacheEntryState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(CacheEntryState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type CacheFilesystemInformation struct {
     AvailableCapacityInBytes int64
     CacheFilesystem CacheFilesystem
@@ -5256,7 +5676,7 @@ func (detailedTapePartition *DetailedTapePartition) parse(xmlNode *XmlNode, aggE
         case "AutoCompactionEnabled":
             detailedTapePartition.AutoCompactionEnabled = parseBool(child.Content, aggErr)
         case "DriveType":
-            parseNullableEnum(child.Content, detailedTapePartition.DriveType, aggErr)
+            detailedTapePartition.DriveType = newTapeDriveTypeFromContent(child.Content, aggErr)
         case "DriveTypes":
             var model TapeDriveType
             parseEnum(child.Content, &model, aggErr)
@@ -5504,6 +5924,16 @@ func (jobStatus JobStatus) StringPtr() *string {
     result := jobStatus.String()
     return &result
 }
+
+func newJobStatusFromContent(content []byte, aggErr *AggregateError) *JobStatus {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(JobStatus)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type MasterObjectList struct {
     Aggregating bool
     BucketName *string
@@ -5997,7 +6427,7 @@ func (namedDetailedTapePartition *NamedDetailedTapePartition) parse(xmlNode *Xml
         case "AutoCompactionEnabled":
             namedDetailedTapePartition.AutoCompactionEnabled = parseBool(child.Content, aggErr)
         case "DriveType":
-            parseNullableEnum(child.Content, namedDetailedTapePartition.DriveType, aggErr)
+            namedDetailedTapePartition.DriveType = newTapeDriveTypeFromContent(child.Content, aggErr)
         case "DriveTypes":
             var model TapeDriveType
             parseEnum(child.Content, &model, aggErr)
@@ -6173,6 +6603,16 @@ func (restOperationType RestOperationType) StringPtr() *string {
     result := restOperationType.String()
     return &result
 }
+
+func newRestOperationTypeFromContent(content []byte, aggErr *AggregateError) *RestOperationType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(RestOperationType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type DatabasePhysicalSpaceState Enum
 
 const (
@@ -6216,6 +6656,16 @@ func (databasePhysicalSpaceState DatabasePhysicalSpaceState) StringPtr() *string
     result := databasePhysicalSpaceState.String()
     return &result
 }
+
+func newDatabasePhysicalSpaceStateFromContent(content []byte, aggErr *AggregateError) *DatabasePhysicalSpaceState {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(DatabasePhysicalSpaceState)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type HttpResponseFormatType Enum
 
 const (
@@ -6256,6 +6706,16 @@ func (httpResponseFormatType HttpResponseFormatType) StringPtr() *string {
     result := httpResponseFormatType.String()
     return &result
 }
+
+func newHttpResponseFormatTypeFromContent(content []byte, aggErr *AggregateError) *HttpResponseFormatType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(HttpResponseFormatType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type RequestType Enum
 
 const (
@@ -6302,6 +6762,16 @@ func (requestType RequestType) StringPtr() *string {
     result := requestType.String()
     return &result
 }
+
+func newRequestTypeFromContent(content []byte, aggErr *AggregateError) *RequestType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(RequestType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type NamingConventionType Enum
 
 const (
@@ -6348,6 +6818,16 @@ func (namingConventionType NamingConventionType) StringPtr() *string {
     result := namingConventionType.String()
     return &result
 }
+
+func newNamingConventionTypeFromContent(content []byte, aggErr *AggregateError) *NamingConventionType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(NamingConventionType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type ChecksumType Enum
 
 const (
@@ -6395,6 +6875,16 @@ func (checksumType ChecksumType) StringPtr() *string {
     result := checksumType.String()
     return &result
 }
+
+func newChecksumTypeFromContent(content []byte, aggErr *AggregateError) *ChecksumType {
+    if len(content) == 0 {
+        // no value
+        return nil
+    }
+    result := new(ChecksumType)
+    parseEnum(content, result, aggErr)
+    return result
+}
 type BucketAclList struct {
     BucketAcls []BucketAcl
 }
diff --git a/ds3/models/responseModels_test.go b/ds3/models/responseModels_test.go
new file mode 100644
index 0000000..ebbf50a
--- /dev/null
+++ b/ds3/models/responseModels_test.go
@@ -0,0 +1,103 @@
+package models
+
+import (
+    "io"
+    "strings"
+    "testing"
+)
+
+type nopCloser struct {
+    io.Reader
+}
+
+func (readCloser *nopCloser) Close() error {
+    return nil
+}
+
+// GOSDK-25 unmarshaling optional enums in response payloads causes panic.
+// This test is for validating the above jira is fixed and to catch future regressions.
+func TestUnmarshalingTapeWithPreviousState(t *testing.T) {
+    responseContent := "<Data><Tape><AssignedToStorageDomain>false</AssignedToStorageDomain>" +
+        "<AvailableRawCapacity>10000</AvailableRawCapacity><BarCode>2f8f0dd0-c1db-4c72-9edc-cd23f7cccd2a</BarCode>" +
+        "<BucketId/><DescriptionForIdentification/><EjectDate/><EjectLabel/><EjectLocation/><EjectPending/>" +
+        "<FullOfData>false</FullOfData><Id>069ad1fb-8c46-4834-a8b1-f92bc9e66059</Id><LastAccessed/>" +
+        "<LastCheckpoint>new</LastCheckpoint><LastModified/><LastVerified/><PartiallyVerifiedEndOfTape/>" +
+        "<PartitionId>d6245cbe-b6ea-46e3-a974-87663016733c</PartitionId>" +
+        "<PreviousState>eject_from_ee_pending</PreviousState><SerialNumber/><State>NORMAL</State>" +
+        "<TakeOwnershipPending>false</TakeOwnershipPending><TotalRawCapacity>20000</TotalRawCapacity><Type>LTO5</Type>" +
+        "<VerifyPending/><WriteProtected>false</WriteProtected></Tape></Data>"
+
+    responseReadCloser := &nopCloser{Reader: strings.NewReader(responseContent)}
+
+    // create the xml tree
+    root, err := parseXmlTree(responseReadCloser)
+    if err != nil {
+        t.Fatalf("expected not to error when parsing xml tree: %v", err)
+    }
+
+    // parse the response
+    var aggErr AggregateError
+    var tapeResponse GetTapesSpectraS3Response
+    tapeResponse.TapeList.parse(root, &aggErr)
+
+    if len(aggErr.Errors) > 0 {
+        t.Fatalf("expected no errors when marshaling, but got %d", len(aggErr.Errors))
+    }
+
+    if len(tapeResponse.TapeList.Tapes) != 1 {
+        t.Fatalf("expected to unmarshal one tape, but got %d", len(tapeResponse.TapeList.Tapes))
+    }
+
+    for _, err := range aggErr.Errors {
+        t.Logf(err.Error())
+    }
+
+    tapeState := tapeResponse.TapeList.Tapes[0].PreviousState
+    if tapeState == nil || *tapeState != TAPE_STATE_EJECT_FROM_EE_PENDING {
+        t.Fatalf("expected tape state to be TAPE_STATE_EJECT_FROM_EE_PENDING, but was '%v'", tapeState)
+    }
+}
+
+// GOSDK-25 unmarshaling optional enums in response payloads causes panic.
+// This test is for validating the above jira is fixed and to catch future regressions.
+func TestUnmarshalingTapeWithoutPreviousState(t *testing.T) {
+    responseContent := "<Data><Tape><AssignedToStorageDomain>false</AssignedToStorageDomain>" +
+        "<AvailableRawCapacity>10000</AvailableRawCapacity><BarCode>2f8f0dd0-c1db-4c72-9edc-cd23f7cccd2a</BarCode>" +
+        "<BucketId/><DescriptionForIdentification/><EjectDate/><EjectLabel/><EjectLocation/><EjectPending/>" +
+        "<FullOfData>false</FullOfData><Id>069ad1fb-8c46-4834-a8b1-f92bc9e66059</Id><LastAccessed/>" +
+        "<LastCheckpoint>new</LastCheckpoint><LastModified/><LastVerified/><PartiallyVerifiedEndOfTape/>" +
+        "<PartitionId>d6245cbe-b6ea-46e3-a974-87663016733c</PartitionId>" +
+        "<PreviousState/><SerialNumber/><State>NORMAL</State>" +
+        "<TakeOwnershipPending>false</TakeOwnershipPending><TotalRawCapacity>20000</TotalRawCapacity><Type>LTO5</Type>" +
+        "<VerifyPending/><WriteProtected>false</WriteProtected></Tape></Data>"
+
+    responseReadCloser := &nopCloser{Reader: strings.NewReader(responseContent)}
+
+    // create the xml tree
+    root, err := parseXmlTree(responseReadCloser)
+    if err != nil {
+        t.Fatalf("expected not to error when parsing xml tree: %v", err)
+    }
+
+    // parse the response
+    var aggErr AggregateError
+    var tapeResponse GetTapesSpectraS3Response
+    tapeResponse.TapeList.parse(root, &aggErr)
+
+    if len(aggErr.Errors) > 0 {
+        t.Fatalf("expected no errors when marshaling, but got %d", len(aggErr.Errors))
+    }
+
+    if len(tapeResponse.TapeList.Tapes) != 1 {
+        t.Fatalf("expected to unmarshal one tape, but got %d", len(tapeResponse.TapeList.Tapes))
+    }
+
+    for _, err := range aggErr.Errors {
+        t.Logf(err.Error())
+    }
+
+    tapeState := tapeResponse.TapeList.Tapes[0].PreviousState
+    if tapeState != nil {
+        t.Fatalf("expected tape state to be nil, but was '%v'", tapeState)
+    }
+}
\ No newline at end of file
diff --git a/ds3/models/responseParsingUtil.go b/ds3/models/responseParsingUtil.go
index dd5a2f3..def60df 100644
--- a/ds3/models/responseParsingUtil.go
+++ b/ds3/models/responseParsingUtil.go
@@ -12,10 +12,10 @@
 package models
 
 import (
-    "strconv"
     "log"
-    "strings"
     "net/http"
+    "strconv"
+    "strings"
 )
 
 // Contains utils used by model parsers to parse response payloads.
@@ -303,4 +303,4 @@ func parseStringSlice(tagName string, xmlNodes []XmlNode, aggErr *AggregateError
         }
     }
     return result
-}
\ No newline at end of file
+}