In Fedora 7 - portmap has been replaced with rpcbind.  They are using 
the tirpc libraries.

rpcbind will by default reject set & unset requests unless the client 
uses a local socket in /var/run/rpcbind.sock.

It is possible to instruct rpcbind to explicitly allow the loopback 
device, but this is not
the default configuration.

I believe pmap_set() and pmap_unset() in the krb5 rpc library needs to 
detect and attempt to use the socket if possible...

I will investigate....

Ezra