--- gnubiff-2.2.15/src/mailbox.cc	2010-02-05 23:54:08.000000000 +0100
+++ gnubiff-2.2.15/src/mailbox.cc	2015-10-11 12:10:10.971392984 +0200
@@ -104,7 +104,7 @@ 
 	g_mutex_unlock (mutex_);
 
 	// Free all mutexes
-	g_mutex_unlock (mutex_);
+	//g_mutex_unlock (mutex_);
 	g_mutex_lock (monitor_mutex_);
 	g_mutex_unlock (monitor_mutex_);
 	g_mutex_free (monitor_mutex_);