I'm still seeing panics.  This is with an Oct 21 MP/i386 kernel.
Typed in by hand, "reboot 0x104" did not dump.

    kernel: trap page page fault, code=0 
    stopped in pid 290.1 process (ntpd) at ...
    > bt
    memset
    ffs_truncate
    VOP_TRUNCATE
    ffs_write
    VOP_WRITE()
    vm_write
    dofilewrite
    sys_write
    syscall_plain
    syscall(number4)

The above panic happened while playing audio, but ntpd took the hit.
The machine seems to be stable enough when compiling or running any
program other than an audio player.  I can compile up a fresh pksrc
for 24+ hours with no problem.  When playing audio it usually takes a
nose dive within an hour.  This is a problem that started happening in
the last 4 months.

    cmpci0 at pci0 dev 11 function 0: C-Media Electronics CMI8738/C3DX PCI Audio Device (rev. 0x10)
    cmpci0: interrupting at irq 10
    audio0 at cmpci0: full duplex, mmap, independent
    opl0 at cmpci0: model OPL3: LR swapped
    midi1 at opl0: CMPCI Yamaha OPL3
    mpu0 at cmpci0
    midi2 at mpu0: CMPCI MPU-401 MIDI UART

I have a jpeg of the screen in case it helps.  (Due to http/jpeg
permissions here, cutting and pasting the URL may be the only way to
see the picture.)

  http://www.wsrcc.com/wolfgang/private/netbsd-ntpd-vop-panic/pic20051024_081118.jpg

-wolfgang
-- 
Wolfgang S. Rupprecht                http://www.wsrcc.com/wolfgang/