--- libaitsched/src/tasks.c	2012/05/31 21:36:40	1.8.2.3
+++ libaitsched/src/tasks.c	2012/05/31 21:48:01	1.8.2.4
@@ -3,7 +3,7 @@
 *  by Michael Pounov <misho@openbsd-bg.org>
 *
 * $Author: misho $
-* $Id: tasks.c,v 1.8.2.3 2012/05/31 21:36:40 misho Exp $
+* $Id: tasks.c,v 1.8.2.4 2012/05/31 21:48:01 misho Exp $
 *
 **************************************************************************
 The ELWIX and AITNET software is distributed under the following
@@ -330,6 +330,10 @@ sched_task_t *
 schedUser(sched_root_task_t * __restrict root, sched_task_func_t func, void *arg, u_long id, 
 		void *opt_data, size_t opt_dlen)
 {
+#ifndef EVFILT_USER
+	sched_SetErr(ENOTSUP, "Not supported kevent() filter");
+	return NULL;
+#else
 	sched_task_t *task;
 	void *ptr;
 
@@ -367,6 +371,7 @@ schedUser(sched_root_task_t * __restrict root, sched_t
 		task = _sched_unuseTask(task);
 
 	return task;
+#endif
 }
 
 /*