When i have a persistence.xml in /src/main/resources/META-INF and in /src/test/resources/META-INF the xml for the test is never used. I found a few issues how to fix this but nobody had an explanation why this behavior is as it is. For me this behavior is really strange (and I couldn't believe that this is not my fault and is really not working). It seem this has to do with classloading - in my opinion, the test classes and the test resources should have priority, otherwise the whole separation of main/test is useless. I hope, that there is no real reason why this is so at the moment, because this behavior is really strange and absolutely against what the normal user would expect.