Index: main/channel.c
===================================================================
--- main/channel.c	(revision 236182)
+++ main/channel.c	(working copy)
@@ -980,7 +980,12 @@
 			ioctl(chan->timingfd, DAHDI_TIMERPING, &blah);
 		}
 #endif				
-	} else if (ast_test_flag(chan, AST_FLAG_BLOCKING)) {
+	} else {
+		ast_log(LOG_WARNING, "Wha? Can't tell the channel that a frame is pending?!\n");
+	}
+	/* Great; we told the channel that a frame is pending.  Now, if the channel
+	 * is blocking, kick it. */
+	if (ast_test_flag(chan, AST_FLAG_BLOCKING)) {
 		pthread_kill(chan->blocker, SIGURG);
 	}