panic: blockable sleep lock (sleep mutex) process lock

Hi!

Latest -current panics on my dual x86 box.
I'm using sched_ule, any ideas?

ps. why doesn't it jump to db> ?

FreeBSD 5.0-CURRENT #0: Mon Apr 14 19:26:10 CEST 2003
    root_at_darkstar:/usr/obj/usr/src/sys/DARKSTAR
-- snip --
SMP: AP CPU #1 Launched!
panic: blockable sleep lock (sleep mutex) process lock _at_
/usr/src/sys/i386/i386/trap.c:728 cpuid = 0; lapic.id = 00000000 Stack
backtrace:
backtrace(c0330e9e,0,c0332f76,cd1e9a54,1) at backtrace+0x17
panic(c0332f76,c033f77e,c032f3b5,c03446e7,2d8) at panic+0x10a
witness_lock(c0eaf068,8,c03446e7,2d8,ffffffff) at witness_lock+0xaf
_mtx_lock_flags(c0eaf068,0,c03446e7,2d8,c0ea95f0) at _mtx_lock_flags+0x64
trap_pfault(cd1e9b4c,0,38,5,38) at trap_pfault+0x9d
trap(18,10,10,c0ea95f0,c0389060) at trap+0x3ad
calltrap() at calltrap+0x5
--- trap 0xc, eip = 0xc01dc367, esp = 0xcd1e9b8c, ebp = 0xcd1e9ba0 ---
sched_choose(c0389060,c0eabc60,0,c0eaf0b8,cd1e9c14) at sched_choose+0x77
choosethread(c0ea95f0,136,c03316b7,c0388f60,3bd36759) at choosethread+0x35
mi_switch(c0ea95f0,68,c01d0550,c0ea95f0,0) at mi_switch+0x17d
msleep(c0381d40,0,68,c032de6b,14) at msleep+0x360
g_waitidle(c0ea95f0,c0ea95f0,c0eaf000,cd1e9d0c,c01a8e17) at g_waitidle+0x5b
vfs_mountroot(c03868a0,0,c032eab1,215,2eaa0) at vfs_mountroot+0xd
start_init(0,cd1e9d48,c032f364,314,0) at start_init+0x47
fork_exit(c01a8dd0,0,cd1e9d48) at fork_exit+0xae
fork_trampoline() at fork_trampoline+0x1a
--- trap 0x1, eip = 0, esp = 0xcd1e9d7c, ebp = 0 ---
Debugger("panic")

Regards
Pawel