I have been experiencing the same kind of crashes with my Kubuntu Oneiric installs. I am using kdm instead of lightdm, but the crash seems very much alike. I will attach a kdm.log. Please let me know if there is anything I can do to help!
** Attachment added: "kdm.log" https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/864010/+attachment/2607296/+files/kdm.log -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/864010 Title: lightdm segfault in libglib after xorg segfault To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/864010/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp