How to enter Rescue mode ?

( just in case you'll ask - sudo gives me segfault -
- this would be another way to try to fix it... http://askubuntu.com/questions/260353/segmentation-fault-when-using-su-or-sudo )

what do you mean by "rescue mode"? you can enter something like a recovery mode by pressing "ctrl-esc-power" instead of only power when switching on, but I guess you know this already if you use a different os.

I mean to get the system into single user mode - a text root console.

I think you have to modify the kernel cmdline for this (e.g. adding "S" or single). At least that was the old SysV way of doing it. Edit /boot/bootimg.cfg and run flash-kernel to do so.

But is there any magic key combination which is read by the bootloader ?
That is - can it be done without a host computer ?

Btw - thanks a lot for the support !

Cheers
Vlad

if you still use the android 2.1 bootloader, you can flash a different kernel (with different kernel cmdline) to the rescure partition and let the bootloader switch. Also there is some "flag" which could be read by the initrd (I guess V2.2 bootloaders do it like this). And a third alternative would be to use u-boot with keyboard support.