>The adbtest works fine, but I can not start X because it does not find any
>displays. It does not boot every time either. Sometimes it hangs on
>"setting tty flags" after fsck.

This used to happen with some Kernels using the old Serial Port code when 
booted with certain devices attached to the printer or modem ports.  You 
might try removing anything that's attached to these ports or disabling 
them in the Booter and see what happens.

-bob