I just did a quick search of the Microsoft Support Database.

If you have the Microsoft Winodws PLUS software pack, it has a Dail-Up Networking SERVER that will manage RAS functions. This software is also avaiable in the Windows Resource Kit which I think is a book and CD that you can find in most bookstores. Windows Resouce Kits can also be downloaded from Microsoft.

Here are some references from the seach for "dail-up networking server".
http://www.microsoft.com/TechNet/win...ote/remote.asp
http://support.microsoft.com/support...dnu_server.asp
http://support.microsoft.com/support.../Q182/6/54.ASP