Has anyone out there gotten this to work? I'm having trouble because Documentum returns an unsecured response to a secured request from the SharePoint 2010 CMIS Consumer web part for the RepositoryService. It's just a Basic WS-Security header, but Documentum's CMIS implementation returns a response with no header, which confuses SharePoint. It shouldn't, and I'm trying to figure out how to tell it that this an ok scenario using this hotfix from Microsoft:
http://support.microsoft.com/kb/971493
But I can't figure out how and where to change the security configuration for SharePoint.