DHCP Clients Not Registering With WINS properly

I've set my DHCP server to distribute the address of a new WINS server -- but the clients continue to register with the old one. 

The clients pick up the new address when they register with DHCP.  That I can see.  I can also see their registrations with the old WINS server. 

Background:  I'm migrating WINS from  Windows Server 2003 SP1  to Windows Server 2008 R2.     The DHCP service has been previously migrated to the Windows Server 2008 R2 computer.  The DHCP service functions there successfully. 

But the clients refuse to register with the new server.

I set up replication between the two servers, just diagnostically, and the replication seems to work.

I wonder where the frames are getting misdirected.

Thanks,

West Coast