I am not sure about this, but I remember that in the 2.2.x kernel, there is feature that prevents the system from halting. If this is the case, see this link:
http://www.diku.dk/hjemmesider/stude.../poweroff.html
I am not familiar with SuSE, so I do not know what kernel version it uses. Are you shutting it down with '/sbin/shutdown -h now'?