NT workstation not receive message from

NT 4.0, one PDC, Two BDC, Five member server.
3 DHCP(node 1 on PDC, node 2 on Remote BDC, node 3 on Printer server.

Problem: When I send message from server manager on PDC(highlight PDC, then go to send message box), only all member servers got message from PDc. All workstations did not get the message at all.

Appreciate any suggestions. Thanks

Eddie