I'm using BIRT with Eclipse Europa (3.3). Talk about a nice reporting tool. Building a report using the design tools was easy and obvious. I hooked it up to one of our Postgres databases (8.2.3) using a type 4 JDBC driver without any problems. A little SQL coding for a query and I was dragging and dropping fields into the report.
Creating customized formats for the duration fields and integrating the report into our application wasn't obvious so I went and bought the only two books available about BIRT.