diff -U3 -r asterisk-1.4.23.1/channels/chan_local.c asterisk-1.4.23.1-ctel/channels/chan_local.c
--- asterisk-1.4.23.1/channels/chan_local.c	2008-12-31 21:20:35.000000000 +0200
+++ asterisk-1.4.23.1-ctel/channels/chan_local.c	2009-03-05 16:39:02.000000000 +0200
@@ -169,7 +169,7 @@
 	other = isoutbound ? p->owner : p->chan;
 
 	/* do not queue frame if generator is on both local channels */
-	if (us && us->generator && other->generator)
+	if (us && us->generator && other && other->generator)
 		return 0;
 
 	/* Set glare detection */