PE2850 multiprocessor freezed under Xorg

[Suken Woo]

lists:
DELL PE2850 freezes with the 5.4-Release SMP GENERIC kernel
while runing X for a few minutes.and it seems caused by Xorg's
bug? https://bugs.freedesktop.org/show_bug.cgi?id=2880

my system msgs and the xorg packages install by FBSD-5.4-RELEASE_disc1
FreeBSD rts.eq.cn 5.4-RELEASE FreeBSD 5.4-RELEASE #2: Wed May 11
09:12:33 CST 2005 wsk@:/usr/obj/usr/src/sys/RTS i386
rts# pkg_info|grep xorg
xorg-clients-6.8.2 X client programs and related files from X.Org
xorg-documents-6.8.2 Documentation of X11 protocol and libraries from X.Org
xorg-fonts-100dpi-6.8.2 X.Org 100dpi bitmap fonts
xorg-fonts-75dpi-6.8.2 X.Org 75dpi bitmap fonts
xorg-fonts-encodings-6.8.2 X.Org font encoding files
xorg-fonts-miscbitmaps-6.8.2 X.Org miscellaneous bitmap fonts
xorg-fonts-truetype-6.8.2 X.Org TrueType fonts
xorg-libraries-6.8.2 X11 libraries and headers from X.Org
xorg-manpages-6.8.2 X.Org library manual pages
xorg-server-6.8.2 X.Org X server and related programs