diff --git a/src/manage_pg.c b/src/manage_pg.c
index 8bcad5351..b39368f7f 100644
--- a/src/manage_pg.c
+++ b/src/manage_pg.c
@@ -870,6 +870,19 @@ manage_create_sql_functions ()
        "$$ LANGUAGE plpgsql"
        " IMMUTABLE;");
 
+  sql ("CREATE OR REPLACE FUNCTION normalize_port ("
+       "  port text)"
+       "RETURNS text AS $$ "
+       "BEGIN"
+       "  CASE"
+       "  WHEN port = 'package'"
+       "  THEN RETURN 'general/tcp';"
+       "  ELSE RETURN port;"
+       "  END CASE;" 
+       "END;"
+       "$$ LANGUAGE plpgsql"
+       " IMMUTABLE;");
+
   /* Functions in SQL. */
 
   if (sql_int ("SELECT (EXISTS (SELECT * FROM information_schema.tables"
diff --git a/src/manage_sql.c b/src/manage_sql.c
index 324ebc143..9c61ab50e 100644
--- a/src/manage_sql.c
+++ b/src/manage_sql.c
@@ -27517,20 +27517,22 @@ init_v2_delta_iterator (report_t report, iterator_t *results, report_t delta,
     "              severity, nvt, results.qod, results.uuid, hostname," 
     "              path, r1_lateral.new_severity as new_severity "
     "       FROM results "
-    "       JOIN (SELECT cvss_base, oid AS nvts_oid from nvts) AS nvts_cols"
+    "       LEFT JOIN (SELECT cvss_base, oid AS nvts_oid from nvts)"
+    "       AS nvts_cols"
     "       ON nvts_cols.nvts_oid = results.nvt"
     "       %s, LATERAL %s AS r1_lateral" 
     "       WHERE report = %llu)"
     " AS r1"
     " FULL OUTER JOIN (SELECT results.*, r2_lateral.new_severity AS new_severity" 
     "                  FROM results" 
-    "                  JOIN (SELECT cvss_base, oid AS nvts_oid from nvts) AS nvts_cols" 
+    "                  LEFT JOIN (SELECT cvss_base, oid AS nvts_oid from nvts)"
+    "                  AS nvts_cols" 
     "                  ON nvts_cols.nvts_oid = results.nvt" 
     "                  %s, LATERAL %s AS r2_lateral" 
     "                  WHERE report = %llu)" 
     " AS r2"
     " ON r1.host = r2.host"
-    " AND r1.port = r2.port" 
+    " AND normalize_port(r1.port) = normalize_port(r2.port)" 
     " AND r1.nvt = r2.nvt "
     " AND (r1.new_severity = 0) = (r2.new_severity = 0)"
     " )",