gdm crashes on 5.1

[Jakob Breivik Grimstveit]

System:

FreeBSD bgjgrimstveit.starshipping.com 5.1-RELEASE-p11 FreeBSD
5.1-RELEASE-p11 #1: Thu Dec 18 10:59:46 CET 2003    
root at bgjgrimstveit.starshipping.com:/usr/obj/usr/src/sys/bgjgrimstveit 
i386

Installed gnome2, XFree86-4 using ports.

Copied /usr/X11R6/etc/rc.d/gdm.sh.sample -> /usr/X11R6/etc/rc.d/gdm.sh

When booting system, it crashes after blinking several times just before
showing login screen (gray gui is being shown a little second).

/var/log/messages output:

Dec 23 13:57:11 bgjgrimstveit kernel: pid 688 (gdm-binary), uid 0:
exited on sig
nal 11
Dec 23 13:57:11 bgjgrimstveit gdm[677]: gdm_cleanup_children: child 688
crashed
of signal 11
Dec 23 13:57:11 bgjgrimstveit gdm[677]: gdm_cleanup_children: Slave
crashed, kil
ling its children
Dec 23 13:57:17 bgjgrimstveit kernel: pid 698 (gdm-binary), uid 0:
exited on sig
nal 11
Dec 23 13:57:17 bgjgrimstveit gdm[677]: gdm_cleanup_children: child 698
crashed
of signal 11
Dec 23 13:57:17 bgjgrimstveit gdm[677]: gdm_cleanup_children: Slave
crashed, kil
ling its children
Dec 23 13:57:25 bgjgrimstveit kernel: pid 708 (gdm-binary), uid 0:
exited on sig
nal 11
Dec 23 13:57:25 bgjgrimstveit gdm[677]: gdm_cleanup_children: child 708
crashed
of signal 11
Dec 23 13:57:25 bgjgrimstveit gdm[677]: gdm_cleanup_children: Slave
crashed, kil
ling its children
Dec 23 13:57:36 bgjgrimstveit kernel: pid 718 (gdm-binary), uid 0:
exited on sig
nal 11
Dec 23 13:57:36 bgjgrimstveit gdm[677]: gdm_cleanup_children: child 718
crashed
of signal 11
Dec 23 13:57:36 bgjgrimstveit gdm[677]: gdm_cleanup_children: Slave
crashed, kil
ling its children
Dec 23 13:57:47 bgjgrimstveit kernel: pid 728 (gdm-binary), uid 0:
exited on sig
nal 11
Dec 23 13:57:47 bgjgrimstveit gdm[677]: gdm_cleanup_children: child 728
crashed
of signal 11
Dec 23 13:57:47 bgjgrimstveit gdm[677]: gdm_cleanup_children: Slave
crashed, kil
ling its children
Dec 23 13:57:48 bgjgrimstveit gdm[677]: The display server has been shut
down ab
out 6 times in the last 90 seconds, it is likely that something bad is
going on.
  I will wait for 2 minutes before trying again on display :0.

Any way I can come around this?

Thanks for any help. Merry Christmas, btw :-)

-- 
Jakob Breivik Grimstveit, http://www.grimstveit.no/~jakob, +47 48298152