--- sys/kern/kern_timeout.c.orig	2009-09-25 09:42:55.007102687 +0900
+++ sys/kern/kern_timeout.c	2009-10-18 19:47:15.537282684 +0900
@@ -201,6 +201,7 @@ start_softclock(void *dummy)
 {
 	struct callout_cpu *cc;
 #ifdef SMP
+	struct intr_event *ie;	/* This can be a member of callout_cpu. */
 	int cpu;
 #endif
 
@@ -210,13 +211,15 @@ start_softclock(void *dummy)
 		panic("died while creating standard software ithreads");
 	cc->cc_cookie = softclock_ih;
 #ifdef SMP
+	intr_event_bind(clk_intr_event, timeout_cpu);
 	for (cpu = 0; cpu <= mp_maxid; cpu++) {
 		if (cpu == timeout_cpu)
 			continue;
 		if (CPU_ABSENT(cpu))
 			continue;
 		cc = CC_CPU(cpu);
-		if (swi_add(NULL, "clock", softclock, cc, SWI_CLOCK,
+		ie = NULL;
+		if (swi_add(&ie, "clock", softclock, cc, SWI_CLOCK,
 		    INTR_MPSAFE, &cc->cc_cookie))
 			panic("died while creating standard software ithreads");
 		cc->cc_callout = NULL;	/* Only cpu0 handles timeout(). */
@@ -224,6 +227,7 @@ start_softclock(void *dummy)
 		    sizeof(struct callout_tailq) * callwheelsize, M_CALLOUT,
 		    M_WAITOK);
 		callout_cpu_init(cc);
+		intr_event_bind(ie, cpu);
 	}
 #endif
 }