I still use a lot of NFS connections on my equipment and when I create OpenVZ VPS systems I need them to have access to NFS. Here are the steps I use:

From the Host Node (HN):

modprobe nfs
vzctl set 101 --features "nfs:on" --save

From the VPS:

yum -y install nfs-utils nfs-utils-lib
chkconfig --levels 345 portmap on
/etc/init.d/portmap start