When using a module that requires JPA transformations, you must start your application server with the Spring instrumentation Java agent. This consist of passing in the following JVM arg:

-javaagent:/path/to/spring-instrument.jar

When using the bundled Ant build scripts, this is taken care of for you - you simply have to configure the path to where the JAR lives on your system in build.properties.

When using a different application server, reference that server's documentation to deterimne the appropriate place to set that argument.