Bug#600599: Additional information
The problem persists with the kernel which entered testing today
(2.6.32-26). Looking back at the logs I see that version 2.6.32-23 was
still working. This one came with the installation, the Debian
installer for testing (Build: 9 October 2010).
Also, I found out that disabling KMS actually make this problem go away. I added
to my boot flags and now the system boots properly. However, with KMS
disabled my monitor loses the signal when X is started, but that's