Please Install the Updated Packages.
Trying to establish an XDMCP session to a machine running xdm would result in a blue screen and an X cursor that could be moved with the mouse but no login greeter. After 2 to 3 minutes, the launching tty would say XDM: too many retransmissions, declaring session dead. This update fixes the issue.
xdm on Mandriva Linux 2008.0, Mandriva Linux 2008.0/X86_64