(Needs 195.36.15) gdm/session killed when jumping to TTY

Binary package hint: xorg

i was using my seesion as usual, jumped to a TTY, and when i tried to get back, X had died and GDM restarted.

Backtrace:
0: /usr/bin/X (xorg_backtrace+0x28) [0x4a25d8]
1: /usr/bin/X (0x400000+0x652dd) [0x4652dd]
2: /lib/libpthread.so.0 (0x7f427f58d000+0xf920) [0x7f427f59c920]
3: /usr/lib/xorg/extra-modules/nvidia_drv.so (_nv001467X+0x16) [0x7f427a23a7f6]
4: /usr/lib/libpixman-1.so.0 (0x7f427eef2000+0xa4a2) [0x7f427eefc4a2]
5: /usr/lib/libpixman-1.so.0 (0x7f427eef2000+0x34859) [0x7f427ef26859]
6: /usr/lib/libpixman-1.so.0 (0x7f427eef2000+0x2ef6b) [0x7f427ef20f6b]
7: /usr/lib/libpixman-1.so.0 (0x7f427eef2000+0x36cc2) [0x7f427ef28cc2]
8: /usr/lib/libpixman-1.so.0 (0x7f427eef2000+0x38030) [0x7f427ef2a030]
9: /usr/lib/libpixman-1.so.0 (0x7f427eef2000+0x2ec6a) [0x7f427ef20c6a]
10: /usr/lib/libpixman-1.so.0 (pixman_image_composite+0x17c) [0x7f427ef21acc]
11: /usr/lib/xorg/modules/libwfb.so (wfbComposite+0x1c0) [0x7f4279d3cbe0]
12: /usr/lib/xorg/extra-modules/nvidia_drv.so (0x7f427a169000+0x32bf65) [0x7f427a494f65]
13: /usr/bin/X (0x400000+0xd7440) [0x4d7440]
14: /usr/bin/X (0x400000+0x164519) [0x564519]
15: /usr/bin/X (0x400000+0x1647e5) [0x5647e5]
16: /usr/bin/X (0x400000+0xa6146) [0x4a6146]
17: /usr/bin/X (0x400000+0x53586) [0x453586]
18: /usr/bin/X (MapWindow+0x179) [0x4576d9]
19: /usr/bin/X (0x400000+0x302d6) [0x4302d6]
20: /usr/bin/X (0x400000+0x30bac) [0x430bac]
21: /usr/bin/X (0x400000+0x2613a) [0x42613a]
22: /lib/libc.so.6 (__libc_start_main+0xfd) [0x7f427e286c4d]
23: /usr/bin/X (0x400000+0x25ce9) [0x425ce9]
Segmentation fault at address 0x752c5

ProblemType: Bug
Architecture: amd64
Date: Tue Mar 9 00:16:42 2010
DistroRelease: Ubuntu 10.04
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Alpha amd64 (20091130)
MachineType: To Be Filled By O.E.M. S37S
NonfreeKernelModules: nvidia
Package: xorg 1:7.5+1ubuntu12
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.32-16-generic root=UUID=56c2b7bf-6ee5-4ec9-a40d-5d27a94d0bd7 ro splash
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.utf8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.32-16.24-generic
SourcePackage: xorg
Uname: Linux 2.6.32-16-generic x86_64
dmi.bios.date: 01/22/2008
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 0801
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: S37S
dmi.board.vendor: To Be Filled By O.E.M.
dmi.board.version: 1.00
dmi.chassis.asset.tag: 0x00000000
dmi.chassis.type: 10
dmi.chassis.vendor: To Be Filled By O.E.M.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr0801:bd01/22/2008:svnToBeFilledByO.E.M.:pnS37S:pvr1.0:rvnToBeFilledByO.E.M.:rnS37S:rvr1.00:cvnToBeFilledByO.E.M.:ct10:cvr1.0:
dmi.product.name: S37S
dmi.product.version: 1.0
dmi.sys.vendor: To Be Filled By O.E.M.
system:
 distro: Ubuntu
 codename: lucidarchitecture: x86_64kernel: 2.6.32-16-generic