Reboot and halt problem

[Rico <coolzone_(_at_)_it_(_dot_)_dk>]

Hi,

I have just updated some of our obsd servers at our datacenter the other 
day.

One of them was via the upgrade procedure on the CD. From 3.6 to 3.7.

Now each time I issue the "reboot" command or the "halt" command, the 
machine reboots and then gives "WARNING: / was not proberly unmounted" 
and it does this each time I reboot or halts it.

What can be causing this?

Thanks,
Rico