Configuring RAS in Exch2k on Win2k Svr

I have a Win2k Server with Exchange 2k.
When configuring a Internet Mail Connector, I cannot get the IMS to use Ras connect. I have Conf a RAS Dialup on modem that works, but it cannot be seen by the Exch Dialup Connection tab.
The tab remains greyed out!
I tried the Phonebook in win2k with no avail!