Thinkpad A21M pxebooting 2.6.11 nfsroot

I have this thinkpad pxebooting but root does not nfs mount.
I have the root exported *(rw,no_root_squash) and tried
mounting it manually from another machine. It mounted
fine!
When the kernel starts booting on the thinkpad I get "unable
to get nfsd port number from server". The kernel NFSroot
option was compiled into the transferred kernel image.
(does this need to be in the server kernel also?)

Remember again another system in the same network can mount.
Portmapper, nfs and dhcp are running on the server.
The file in pxelinux.cfg contains an append with
nfsroot=192.168.0.33:/tftpboot/alpha (which is the target
server.

DHCP has done its job configuring the interface etc otherwise
it would not be booting the kernel. It has an option for
root-path and the above directory.
Any thoughts appreciated.
-Walt

maybe a more sorted description is in order..

Server exports a particular directory over NFS fine.
When a network booted kernel (with Root over NFS compiled
in) asks for its root (that same directory) to be mounted
the answer comes back ...
"unable to get nfsd port number from server using default"
server side portmap,nfs and dhcp are running.
Any ideas how I can provoke more info or why the portmapper
would not acknowledge?

Thanks.
-Walt