Index: generic/include/ipc/ipc.h
===================================================================
--- generic/include/ipc/ipc.h	(revision d1e414c63e2033f906d3c12947392b421a0998d6)
+++ generic/include/ipc/ipc.h	(revision 2f7342d12561f9ee108f176359ac9eaea16c4e7c)
@@ -84,4 +84,5 @@
 	answerbox_t *callerbox;
 	int flags;
+	task_t *sender;
 	__native data[IPC_CALL_LEN];
 } call_t;
Index: generic/include/proc/task.h
===================================================================
--- generic/include/proc/task.h	(revision d1e414c63e2033f906d3c12947392b421a0998d6)
+++ generic/include/proc/task.h	(revision 2f7342d12561f9ee108f176359ac9eaea16c4e7c)
@@ -41,4 +41,6 @@
 	link_t tasks_link;	/**< Link to other tasks within the system. */
 	as_t *as;		/**< Address space. */
+	task_id_t taskid;           /**< Unique identity of task */
+
 	/* IPC stuff */
 	answerbox_t answerbox;  /**< Communication endpoint */
Index: generic/include/syscall/syscall.h
===================================================================
--- generic/include/syscall/syscall.h	(revision d1e414c63e2033f906d3c12947392b421a0998d6)
+++ generic/include/syscall/syscall.h	(revision 2f7342d12561f9ee108f176359ac9eaea16c4e7c)
@@ -38,4 +38,5 @@
 	SYS_IPC_CALL_ASYNC_FAST,
 	SYS_IPC_CALL_ASYNC,
+	SYS_IPC_ANSWER_FAST,
 	SYS_IPC_ANSWER,
 	SYS_IPC_WAIT,
Index: generic/include/typedefs.h
===================================================================
--- generic/include/typedefs.h	(revision d1e414c63e2033f906d3c12947392b421a0998d6)
+++ generic/include/typedefs.h	(revision 2f7342d12561f9ee108f176359ac9eaea16c4e7c)
@@ -38,4 +38,6 @@
 typedef unsigned long count_t;
 typedef unsigned long index_t;
+
+typedef unsigned long long task_id_t;
 
 typedef struct config config_t;