Mark Doliner has forked JCoverage to create Cobertura, a free-as-in-speech (GPL) code coverage tool for Java. I'm not sure this is so much of a fork as it is picking up an abandoned project and running with it. The sample output looks solid, not quite as polished as Clover's output, but functional and readable. It is a little embarrassing just how little of Cobertura's own code is covered by unit tests.
The Eclipse Project has posted Eclipse 3.1M5a to fix a bug that slipped out in 3.1M5. If you've already downloaded 3.1M5, download 3.1M5a.
Nathan Fiedler has released version 2.33 of JSwat, a graphical, stand-alone Java debugger built on top of the Java Platform Debugger Architecture. Features include breakpoints, source code viewing, single-stepping, watching variables, viewing stack frames, and printing variables. Version 2.33 fixes bugs. JSwat is published under the GPL.
The Jakarta Apache Project has posted version 5.5.8 of the Tomcat 5.5.8 open source servlet container and the official reference implementation of the Java Servlet API 2.4 and Java Server Pages (JSP) 2.0. The version numbering is funky but this is basicaly an alpha release after the 5.5.7 production release. (Why, oh why, can't they just call this 5.6 alpha 1 like any sane devloper would?) 5.5.8 mostly fixes bugs. "Tomcat 5.5 is designed to run on J2SE 5.0 and later, and requires configuration to run on J2SE 1.4....In addition, Tomcat 5.5 uses the Eclipse JDT Java compiler for compiling JSP pages. This means you no longer need to have the complete Java Development Kit (JDK) to run Tomcat, but a Java Runtime Environment (JRE) is sufficient. The Eclipse JDT Java compiler is bundled with the binary Tomcat distributions. Tomcat can also be configured to use the compiler from the JDK to compile JSPs, or any other Java compiler supported by Apache Ant."