One of our customers in the Philippines recently requested for a multi-master replication over the WAN for their Sun Java System Directory Server deployment.
This is a government tax-collecting agency. We have been supporting them for a long time.
I did a feasibility study and found that they have real old version of Directory Server 5.1 installed. I did a due diligence to make sure that Directory Server 5.1 is still supported. Otherwise, this MMR exercise should include an upgrade to the latest release of Sun Java Directory Server prior to MMR configuration.
They are lucky. Directory Server 5.1 is still under limited support until 2011.
More information here.