Under some circumstances Maven "forgets" about test dependencies in multi-module builds. The affected module can be build only if the build is started from its local project directory. If the build is run from a parent directory, the test fails because of missing classes. This issue applies to M207 and recent M208-RC1, the project can be build without problems with M205 (M206 is completely bogus). The problem was for us already the show stopper for M207 and I thought with some of the now resolved issues it has been gone, but I was wrong. I did not report it earlier, because I was never able to reproduce the problem with a minimal build ... until now and it took me about 3 days to create a demonstrating multi module project.