Problem rebooting RS/6K b50 SUSE 7.1

Good afternoon Linux experts, I have an apparently dumb problem rebooting my IBM RS/6k b50 running SUSE 7.1 . Doing this without keyboard, mouse and display (using a telnet terminal) the machine come to 0c5 (LCD display) and stops waiting for an 'enter' for ever. It seems a yaboot problem, in fact when the yaboot timeout occurs yaboot issues an error message and asks " press enter to continue".... (I connected a console to the box to be able to read the message obviously) This is a big problem if someone want to put the box into an unattended web farm.... SUSE 7.0 worked fine... Is there someone able to fix this bug or to find a workaround? Thanks in advance and best Regards Alberto Milano ITALY