PC: Dell Optiplex 7010 BIOS version A16
System: SLED11 SP3 x86_64 3.0.101-0.15-default

Problem: after a "shutdown -h now" the system restarts. This is annoying
as student's PCs are supposed to be powered off at night and are shut
down with the help of a cron script. A very similar installation did
work well with an Optiplex 745 in 32 bit mode.
Is this a known problem with this hardware and kernel? Anything I can do
about it, kernel parameters or BIOS settings?