[CentOS] reading ufs2 filesystems with centosplus kernel

Hello,
    I'm running centos5 with the centosplus kernel v2.6.18-8.1.8.el5 and i'm 
trying to read a drive that has a ufs2 partition on it. It was originally in 
a FreeBSD machine and has some data i'd like to get at. Googling indicated 
this should work with the command:

mount -r -t ufs -o ufstype=ufs2 <device> <mountpoint>

device is /dev/hdb5 and mountpoint is /mnt. I'm getting an error unknown 
filesystem type ufs. I'm assuming i have to load a module of some kind. Any 
help appreciated.
Thanks.
Dave.