vboxdrv failed because of vga_switcheroo

[Jean Demange]

I'm running ubuntu 11.04 with 3.0.4-030004-generic kernel. My computer is an acer timeline 5810 with a dual graphic card (ati+intel). I'm using vga_switcheroo in order to switch off my ati card.

I'm trying to use the repository version of virtualbox (4.0.4). The installation goes well but when it charges modules, X bugs and I see the terminal. At each start up, I can see gdm but 5 seconds later, X bugs and I see the terminal too. I can continue to use the X session but typing ctrl+alt+f1 and then ctrl+alt+f7. But every command in relation with modules failed (modprobe -l, lsmod, ...).
I join the part of the kern.log in relation with this issue.

Thanks.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: virtualbox-ose (not installed)
Uname: Linux 3.0.4-030004-generic x86_64
Architecture: amd64
Date: Wed Sep 7 16:20:33 2011
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110427.1)
ProcEnviron:
 LANGUAGE=fr_FR:fr:en
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
SourcePackage: virtualbox-ose
UpgradeStatus: No upgrade log present (probably fresh install)