KDM, Session declined No valid address

I am running Suse Linux 10.0. I upgraded from Suse Linux 9.1. I have several diskless PCs running as X workstations. When I had Suse Linux 9.1, kdm launched and the user at the X workstation was greeted with a nice login screen. After the upgrade to Suse Linux 10.0, the X workstations are reporting the following error "XDMCP fatal error: Session declined No valid address". I have spent hours trying to correct this problem. Any insight or help ? Much of the information on the Internet for XDMCP is for older versions of Suse (7.X), etc, nothing current. Ken Cobler