@ Greg Taylor
Yes I am aware of the situation but had no choice other than taking the support of Outlook247, as we have 8 companies and each company GAL should not be visible to other company users. MS did not give us a solution for 3 Months. The solution was good enough and our exchange 2010 holds more than 2300 mailboxes with heavy useage.
I think what Sasha2011 wants is, he currently has a setup with resource forest with exchange 2003, and has implemented GAL segrigation. Now he wants to transition to exchange 2010, and keep the GAL segrigation the way it was on exchange 2003.
He would have no issues with GAL in Webmail/OWA as it is from "msexchquerybasedn" attribute for the user to populate but when it comes to GAL in MAPI it is from "showInAddressBook"
Thanks