fsck_ufs after every reboot

[O. Hartmann]

I run FreeBSD 8.0/AMD64 on two boxes (one is a UP older AMD64 Athlon64 
3500, other an 8-Core Dell Poweredge 1950).

After nearly every reboot the box does fsck on all UFS2 filesystems. In 
most cases, while shuting down, the box reports about not willing to die 
processes and after a reboot, the filesystems are unclean.

Is this a common problem at the moment or special?

Regards,
Oliver