PGUnit is a xUnit-style framework for stored procedures in PostgreSQL 8.3+. It allows database developers to write automated tests for stored procedures or use TDD concepts. Tests are executed within automatically rolled-back transactions.
The Stored procedures unit-test frameworkproject is a PostgreSQL Community project that is a part of the pgFoundry.
The pgFoundry page for the project is at http://pgfoundry.org/projects/pgunit, where you can find downloads, documentation, bug reports, mailing lists, and a whole lot more.