We still recommend at least "PostgreSQL 7.3 or 7.4". 7.4 is now seven years old and losing maintainer support next month (or so). By December only 8.2 and up will be supported.
Sun Java 5 SE reaches its End Of Service Life in October 2010.
Maven 2.2 is current. We might recommend at least 2.0.11 (the current "older release") rather than 2.0.8.
Tomcat 4 is positively ancient and definitely unsupported by its maintainers. Even 5.0 is too old for help. 5.5 should be our minimum recommendation.