--- zzzz-none-000/linux-2.6.28.10/kernel/posix-cpu-timers.c	2009-05-02 18:54:43.000000000 +0000
+++ puma5-6360-529/linux-2.6.28.10/kernel/posix-cpu-timers.c	2010-04-06 14:20:33.000000000 +0000
@@ -1002,6 +1002,8 @@
 		list_move_tail(&t->entry, firing);
 	}
 
+	if (unlikely(!sig))
+		return;
 	/*
 	 * Check for the special case thread timers.
 	 */
@@ -1327,6 +1329,9 @@
 	}
 
 	sig = tsk->signal;
+	if (unlikely(!sig))
+		return 0;
+
 	if (!task_cputime_zero(&sig->cputime_expires)) {
 		struct task_cputime group_sample;