Can't login after update.

fengtou

I update my ubuntu 7.04 with Synaptic Package Manger yesterday.
I remember that totally include 3 package, It seems that 2 relate kernel, one is nvidia-glx update.
but when restart my pc, I can't login my session in my username any more,
How can I login with my username?


Error Information as below:

Your session only lasted less than 10 seconds, If you have not logged out yourself,
this could mean that there is some installation problem or that you may be out of
diskspace. try logging with one of the failsafe sessions to see if you can fix this problem.

View details (~/.Xsession-errors file)

/etc/gdm/PreSession/Default: Registering your session with wtmp and utmp
/etc/gdm/PreSession/Default: running: /usr/X11R6/bin/session -a -w /var/log/wtmp -v
/var/X11R6/bin/session -a -w /var/log/wtmp -v /var/run/vtmp/ -x "var/lib/gdm/: 0.Xservers " -h " " -l " :0 "username" /etc/ gdm/Xsession:Beginning session setup
export:24 : : bad variable name