If your organization deployed Microsoft Exchange Server 2007 in a cross-forest topology, you must implement synchronization of the following attributes for Office Communications Server 2007 R2 when deployed in a central forest.

You must synchronize the contact object in the central forest and the mailbox in the Exchange Server forest.

The following attributes must be synchronized from the user object to the contact object.

• ObjectSid
  
  
• telephoneNumber
  
  
• displayName
  
  
• givenName
  
  
• sn (surname)
  
  
• physicalDeliveryOfficeName
  
  
• l (city)
  
  
• st (state)
  
  
• Country
  
  
• Title
  
  
• Mail
  
  
• Company
  
  
• Cn
  
  

ImportantThe primary user address (msRTCSIP-PrimaryUserAddress) of the contact (SIP URI) must be added to the list of proxy addresses in the ProxyAddresses attribute of the user object in both forests. This is required for integration with Outlook and other Microsoft Office products.

Table 5 shows how attributes are mapped from a user object to a contact object using the example user, User A.

Table 5. Attributes on User and Contact Objects

The following attributes must be synchronized across forests for distribution group expansion to work in a cross-forest scenario.

• ObjectSid
  
  
• Mail
  
  
• displayName
  
  
• groupType
  
  

Table 6 shows how attributes are mapped from a user object to a contact object using the example group, Group A.

Table 6. Attributes on Group and Contact Objects

For group to contact synchronization, the attribute msDS-SourceObjectDN on the contact should be populated with the DN (distinguished name) of the group that is used in the forest where the group is managed.