You may remember that opensource.bamboo.atlassian.com would fail to build struts2, failing because java couldn't be found by sub-processes. This was fixed by explicitly setting the path to include the default java.

However this raises the question of whether the build/tests are being run with the correct java SDK. For example, if I have JDK1.5 installed system-wide but nominate to build with JDK1.4 it is likely that JDK1.5 will run unit-tests (and possibly build the project?) rather than the nominated build environment, as maven2 doesn't explicitly specify the java executable path, and the default javac/java will be picked-up.

A possible solution is to add the $JAVA__HOME/bin to the start of the path.