Index: kernel/generic/src/ipc/ipc.c
===================================================================
--- kernel/generic/src/ipc/ipc.c	(revision 103de761c76f48e9f038d2204626d4ec657b81d1)
+++ kernel/generic/src/ipc/ipc.c	(revision e701eb11c1bab3bbb6c9ec77eae0aff69273dfdf)
@@ -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