FreeBSD 5.1-BETA fatal trap 12 during setup

Hi,

I got this when running Upgrade on FreeBSD 5.1-BETA setup program,
selecting an xl0 as my ethernet device and connecting to ftp.freebsd.org
to download everything:

Fatal trap 12: page fault while in kernel mode
fault virtual address	= 0x0
fault code		= supervisor read, page not present
instruction pointer	= 0x8:0xc0300d73
stack pointer		= 0x10:0xd7b95ae0
frame pointer		= 0x10:0xd7b95b00
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, def32 1, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= 42 (syncer)

and in the actual setup window I see:
kernel: type 12 trap, code=0
Stopped at	_mtx_lock_flags+0x43:	cmpl	$0xc054508c,0(%ebx)
db>

I can continually reproduce this, so if someone wants me to do further
debugging, I will. Do CC me on replies; I'm not subscribed to this
mailing list.

Regards,
Josh

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