Incremental sync fails when adding memberships to an LDAP server via a Remote Crowd

Steps to reproduce:

• Need an LDAP directory (with some test users and groups) and two crowd servers (A and B)
• Create a Cached Directory in Crowd A pointing to the LDAP directory
• Synchronize Crowd A.
• Create an Application in Crowd A with the LDAP directory in it.
• Create a Remote Crowd directory in Crowd B pointing to the Crowd A Application
• Synchronize Crowd B. It should do a full sync as the first sync.
• Add a group membership to LDAP directory (i.e. add a user to a group).
• Synchronize Crowd A, then Synchronize Crowd B.
• Crowd B should do an incremental sync.

Expected Result:

Incremental Sync for Crowd B succeeds.

Actual Result:

Incremental Sync for Crowd B fails with a MembershipAlreadyExistsException.