The EnterpriseDB folk <a href="http:&#x2F;&#x2F;www.enterprisedb.com&#x2F;products-services-training&#x2F;products-overview&#x2F;xdb-replication-server-multi-master" rel="nofollow">http:&#x2F;&#x2F;www.enterprisedb.com&#x2F;products-services-training&#x2F;produ...</a> and 2ndQuadrant <a href="http:&#x2F;&#x2F;2ndquadrant.com&#x2F;en-us&#x2F;resources&#x2F;bdr&#x2F;" rel="nofollow">http:&#x2F;&#x2F;2ndquadrant.com&#x2F;en-us&#x2F;resources&#x2F;bdr&#x2F;</a> both have multi-master replication.