DHCP problem

hello I.T friends,

i configured a RAS server on a PDC which also have a DHCP service enabled. in the DHCP manager i created another server apart from the local machine server.i also created a scope *.*.*.51 to *.*.*.80. a global DHCP option was completed.

everything seems to be okay. remote users do connect to the win nt4 server,PDC and access the internet.

but the main problem is that the event viewer is alwyas given me this warning message
“The DHCP server issued a NACK to the client (00CF48D801524153208056FF3A1199C00107000000) for the address (216.72.207.85) request.”

i have tried everything i could.

pls. try to help me out.

lolu