Reiserfs partition problem

I'm bringing up a server to run CommuniGate Pro (nice, BTW) under RH 7.1
and was wondering if anyone has heard of this offhand: at shutdown, if
I haven't dismounted the reiserfs partition the system hangs trying to
unmount filesystems.

I admittedly haven't RTFM. If the infernal Windows viruses will give me
a break for 10 minutes I hope to today :(

It's a 75GB partition, the fstab entry is

/dev/sda11 /var/CommuniGate reiserfs defaults 1 2

Thanks for taking a look :-)

Steve