Another great tool from Mike Shughrue has been published on CodePlex: http://www.codeplex.com/PS2007ADResSync
From the documentation contained in the utility (zip file):
OverviewThe out of the box active directory sync for Project Server 2007 only moves a fixed set of fields from AD to Project Server. In some cases, additional AD fields need to be mapped to resource custom fields. The ResourceSync service can be run after the out of the box AD sync to move the additional AD fields.
Source CodeThe source code is contained in a solution called ResourceSync in these 5 projects: