Adding a Global Group

Does anyone know of a way to add a global group from an NT 4 PDC to a domain local group in AD through a program? I would like to be able to interate through the global groups on an NT 4 PDC that has full trusts established with our 2003 AD and add each group to an existing domain local group on the AD. I can accomplish this via the gui, but I would like to accomplish this programmatically.

Thanks.