rpcbind is not working on Suse 11 only portmap alone

[Peper]

Hi Folks,

I'm on Sless 11. Have all default settings.
Configuring db2 server +client with sharing folder, using rsh.
So, on the server I also installed nfs-server.
Was able to mount. Can host and rsh all nodes (2+2)

But I cannot even start nodes from client.
Getting
Error encountered in TCP/IP protocol support or
Mapping issue

After I browsing Forum I found that if I unsinatll rpcbind and install portmap it could help.
I did that AND IT HELPED!

when I'm switching back I again lost a connection (sometimes it is working fine for a while but then server trying to ping client but even in server logs I can see Client is timing out)

But I want to understand why. As rpcbind contain the same portmap pcg. So, may be I'm not configuring correctly rpcbind?
Or may be I need to enable/disable something?