ipv6 enabled and panic in 7.4-RELEASE

[nick]

Hello list,

I enabled ipv6 in a server running 7.4-RELEASE with amd64 generic
kernel, and bge. I issued a static ipv6 address with prefix lenght 120
(according to my network administrator) and ipv6 default route in
rc.conf, and issued '/etc/rc.d/network_ipv6 start'.

ifconfig bge0:
bge0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=9b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM>
        ether 00:f5:0b:3d:3b:e4
        inet6 fe80::217:a4ff:fe8d:33e8%bge0 prefixlen 64 scopeid 0x1
	(ipv4 stuff)
        inet6 2a02:1823:1002:b1 prefixlen 120 (this is the static address)
        media: Ethernet autoselect (100baseTX
<full-duplex,flowcontrol,rxpause,txpause>)
        status: active

I enabled inet6 rules and in /etc/pf.conf like this:

pass  in  on $ext_if inet6 proto tcp from any to $ext_if port http
pass  out on $ext_if inet6 proto tcp all
pass out on $ext_if inet6 proto icmp6 all icmp6-type echoreq keep state
pass in on $ext_if inet6 proto icmp6 all icmp6-type echoreq

Locally, ipv6 seemed to work OK as I could ping6 localhost and hostname.
However, ipv6 connections from outside were still being blocked by pf,
so I was trying to solve that issue.
At one point, I did a 'ping6 ipv6.google.com', after which the machine
dropped the ssh connection. I connected to the console using ILO, only
to see it rebooting. It was writing vmcore.0 at that point, which I
interrupted using ctr-c, since I was not sure how long it would take.

Now I have those files in /var/crash:
bounds
info.0
minfree
vmcore.0

info.0 contains:
Dump header from device /dev/da0s1b
  Architecture: amd64
  Architecture Version: 2
  Dump Length: 1812742144B (1728 MB)
  Blocksize: 512
  Dumptime: Wed Jun  8 12:56:40 2011
  Hostname: server
  Magic: FreeBSD Kernel Dump
  Version String: FreeBSD 7.4-RELEASE #0: Fri Feb 18 01:55:22 UTC 2011
    root at driscoll.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC
  Panic String: page fault
  Dump Parity: 2017522204
  Bounds: 0
  Dump Status: good

The size of vmcore.0 is 767M. It is probably incomplete.

In /var/log/messages I have:
Jun  8 12:59:31 server savecore: reboot after panic: page fault
Jun  8 12:59:31 server savecore: writing core to vmcore.0

I have not built a kernel locally, so will I be able to read the
vmcore.0 using kgdb without local sources?

Not sure if I can submit a PR for this either, thus I would like to
learn more about this issue at first. I searched the freebsd bugs
database, but found nothing really similar.

Any help about how to handle this issue would be much appreciated.

nick