I'm using Datanucleus to enhance classes, and have my annotationed classes in a separate domain jar ( built by Maven ). When the domain jar is imported into an Intellij project ( Maven style), Intellij reports the classes from the domain jar as being in error, and show up red, because they don't implement jdoIsPersistent. This seemed to start after moving to Java7. The project builds fine using maven inside or outside of Intellij. Does any one know of a solution?