I have a department with a 5.5 Exchange server that they need to upgrade. It currently synchronises its GAL with a head office 2003 server. The department 5.5 server is in a different forest/domain to the head office server and currently successfully synchronises its GAL using a 5.5 Connector (and probably an AD Connector). The head office wants to consume the 5.5 server into their forest but this is not an option. How do I upgrade the department's 5.5 server (which I have full access to) so that it can still synchronise its GAL with the head office 2003 server (which I have no access to and only some cooperation from their techies)?
