Index: channel.c
===================================================================
RCS file: /usr/cvsroot/asterisk/channel.c,v
retrieving revision 1.259
diff -u -r1.259 channel.c
--- channel.c	11 Nov 2005 03:48:28 -0000	1.259
+++ channel.c	16 Nov 2005 19:07:41 -0000
@@ -667,7 +667,11 @@
 int ast_queue_hangup(struct ast_channel *chan)
 {
 	struct ast_frame f = { AST_FRAME_CONTROL, AST_CONTROL_HANGUP };
-	chan->_softhangup |= AST_SOFTHANGUP_DEV;
+	/* Yeah, let's not change a lock-critical value without locking */
+	if (!ast_mutex_trylock(&chan->lock)) {
+		chan->_softhangup |= AST_SOFTHANGUP_DEV;
+		ast_mutex_unlock(&chan->lock);
+	}
 	return ast_queue_frame(chan, &f);
 }