http://blogs.esri.com/Dev/blogs/geodatabase/archive/2008/05/16/Road-Ahead-_2D00_-PostgreSQL-8.3.0-database-support-at-ArcGIS-9.3.aspxThe following post was written by Kasia Tuszynska, a product engineer on geodatabase team specializing in PostgreSQL and the geodatabase. The release of ArcGIS 9.3 will see an addition to the list of databases supported by ArcSDE. PostgreSQL 8.3.0 isenCommunityServer 2.1 SP2 (Debug Build: 61120.2)