diff --git a/src/iface.c b/src/iface.c
index 3ebebee..6c8bfd6 100644
--- a/src/iface.c
+++ b/src/iface.c
@@ -962,7 +962,7 @@ static void delete_group_cb(int timeout, void *arg)
 
     ifi = config_find_iface(cbk->ifindex);
     if (!ifi)
-	goto done;
+	return;
 
     logit(LOG_DEBUG, 0, "Group membership timeout for %s on %s",
 	  inet_fmt(cbk->g->al_addr, s1, sizeof(s1)), ifi->ifi_name);
@@ -977,8 +977,6 @@ static void delete_group_cb(int timeout, void *arg)
 
     TAILQ_REMOVE(&ifi->ifi_groups, g, al_link);
     free(g);
-  done:
-    free(cbk);
 }
 
 /*
@@ -987,7 +985,9 @@ static void delete_group_cb(int timeout, void *arg)
 static int delete_group_timer(int ifindex, struct listaddr *g, int tmo)
 {
     cbk_t *cbk;
+    int tid;
 
+    /* cbk is freed as a side effect of pev_timer_del (via the deletion cb) */
     cbk = calloc(1, sizeof(cbk_t));
     if (!cbk) {
 	logit(LOG_ERR, errno, "%s(): Failed allocating memory", __func__);
@@ -1000,7 +1000,10 @@ static int delete_group_timer(int ifindex, struct listaddr *g, int tmo)
     /* Record mtime for IPC "show igmp" */
 //    g->al_mtime = virtual_time;
 
-    return pev_timer_add(tmo * 1000000, 0, delete_group_cb, cbk);
+    tid = pev_timer_add(tmo * 1000000, 0, delete_group_cb, cbk);
+    pev_timer_set_cb_del(tid, free);
+
+    return tid;
 }
 
 /*
diff --git a/src/pev.c b/src/pev.c
index 1aaa28a..e1b7298 100644
--- a/src/pev.c
+++ b/src/pev.c
@@ -35,6 +35,7 @@ struct pev {
 	};
 
 	void (*cb)(int, void *);
+	void (*cb_del)(void *);
 	void *arg;
 };
 
@@ -97,6 +98,21 @@ int pev_sig_del(int id)
 	return pev_sock_del(id);
 }
 
+int pev_sig_set_cb_del(int id, void (*cb)(void *))
+{
+	struct pev *entry;
+
+	entry = pev_find(PEV_SIG, id);
+	if (!entry) {
+		errno = ENOENT;
+		return -1;
+	}
+
+	entry->cb_del = cb;
+
+	return 0;
+}
+
 /******************************* SOCKETS ******************************/
 
 static int nfds(void)
@@ -157,6 +173,9 @@ int pev_sock_del(int id)
 			entry->active = 0;
 			sig_handler(0);
 
+			if (entry->cb_del)
+				entry->cb_del(entry->arg);
+
 			return 0;
 		}
 	}
@@ -200,6 +219,22 @@ int pev_sock_close(int sd)
 	return 0;
 }
 
+int pev_sock_set_cb_del(int id, void (*cb)(void *))
+{
+	struct pev *entry;
+
+	for (entry = pl; entry; entry = entry->next) {
+		if (entry->id == id) {
+			entry->cb_del = cb;
+
+			return 0;
+		}
+	}
+
+	errno = ENOENT;
+	return -1;
+}
+
 /******************************* TIMERS *******************************/
 
 static struct pev *timer_ffs(void)
@@ -396,6 +431,11 @@ int pev_timer_get(int id)
 	return -1;
 }
 
+int pev_timer_set_cb_del(int id, void (*cb)(void *))
+{
+	return pev_sock_set_cb_del(id, cb);
+}
+
 /******************************* GENERIC ******************************/
 
 static struct pev *pev_new(int type, void (*cb)(int, void *), void *arg)
diff --git a/src/pev.h b/src/pev.h
index 314d381..ad4589b 100644
--- a/src/pev.h
+++ b/src/pev.h
@@ -33,6 +33,12 @@ int pev_run        (void);
 int pev_sig_add    (int signo, void (*cb)(int, void *), void *arg);
 int pev_sig_del    (int id);
 
+/*
+ * Destructor callback, called when deleting a signal event (pev_sig_del).
+ * Useful for deallocating heap allocated arg data.
+ */
+int pev_sig_set_cb_del  (int id, void (*cb)(void *));
+
 /*
  * Socket or file descriptor callback by sd/fd, only one callback per
  * descriptor.  API changes to CLOEXEC and NONBLOCK.  Delete by id
@@ -48,6 +54,12 @@ int pev_sock_del   (int id);
 int pev_sock_open  (int domain, int type, int proto, void (*cb)(int, void *), void *arg);
 int pev_sock_close (int id);
 
+/*
+ * Destructor callback, called when deleting a socket event (pev_sock_del or
+ * pev_sock_close). Useful for deallocating heap allocated arg data.
+ */
+int pev_sock_set_cb_del  (int id, void (*cb)(void *));
+
 /*
  * Periodic timers use SIGALRM via setitimer() API, may affect use of
  * sleep(), usleep(), and alarm() APIs.  See your respective OS for
@@ -80,4 +92,10 @@ int pev_timer_del  (int id);
 int pev_timer_set  (int id, int timeout);
 int pev_timer_get  (int id);
 
+/*
+ * Destructor callback, called when deleting a timer (pev_timer_del).
+ * Useful for deallocating heap allocated arg data.
+ */
+int pev_timer_set_cb_del  (int id, void (*cb)(void *));
+
 #endif /* PEV_H_ */