strange NFS failure

[Robin P. Blanchard]

> just upgraded two systems to RELENG_5 this evening and NFS 
> client has collapsed.  is this known issue?  apologies -- i 
> realise i should really be tracking stable list.
> 
> the error is
> 
>      [udp] 10.12.12.66:/usr/cabinet: RPCPROG_NFS: RPC: Port 
> mapper failure -
> RPC: Unable to recieve
> 
> and yes rpcbind is running OK.  rpcinfo of the system 
> produces normal output.
> 
> thanks for any pointers.

Sounds related to:
http://lists.freebsd.org/mailman/htdig/freebsd-stable/2005-June/015726.html

Using "broken" kernel also yields "broken" nfs...