Index: kernel/generic/src/ipc/ipc.c
===================================================================
--- kernel/generic/src/ipc/ipc.c	(revision 20c7c409c4e0f6659393f1e3894d868d27facc21)
+++ kernel/generic/src/ipc/ipc.c	(revision 64aed801661710342dc9ccfde9883a75fd31dc6c)
@@ -583,6 +583,8 @@
 		for (i = 0; i < IPC_MAX_PHONES; i++) {
 			if (TASK->phones[i].state == IPC_PHONE_HUNGUP &&
-			    atomic_get(&TASK->phones[i].active_calls) == 0)
+			    atomic_get(&TASK->phones[i].active_calls) == 0) {
 				TASK->phones[i].state = IPC_PHONE_FREE;
+				TASK->phones[i].callee = NULL;
+			}
 			
 			/* Just for sure, we might have had some