--- asterisk-11.2.1/channels/chan_unistim.c	2012-10-15 01:11:45.000000000 -0700
+++ asterisk-11.2.1-custom/channels/chan_unistim.c	2013-02-06 17:00:43.000000000 -0800
@@ -4641,6 +4641,7 @@
 	ast_mutex_lock(&sub->parent->parent->lock);
 	if (!sub->parent->parent->session) {
 		ast_log(LOG_WARNING, "Unistim callback function called without a session\n");
+		ast_mutex_unlock(&sub->parent->parent->lock);
 		return NULL;
 	}
 	ast_mutex_unlock(&sub->parent->parent->lock);
@@ -5074,6 +5075,7 @@
 	if (p->owner != oldchan) {
 		ast_log(LOG_WARNING, "old channel wasn't %s (%p) but was %s (%p)\n",
 				ast_channel_name(oldchan), oldchan, ast_channel_name(p->owner), p->owner);
+		ast_mutex_unlock(&p->lock);
 		return -1;
 	}