reboot: PROM prompt loops

[Andreas Jaehnigen <jaehnias@ims.uni-stuttgart.de>]

Hi there,

if I reboot my Sun SLC here with
	reboot -f
it starts rebooting. Then the PROM prompt is displayed in an endless loop:

type b (boot), c (continue) or n (new command mode)
type b (boot), c (continue) or n (new command mode)
type b (boot), c (continue) or n (new command mode)
type b (boot), c (continue) or n (new command mode)
...

The machine is booted via TFTP and gets all its partitions over NFS.

Any clues..??