I am writing an Eclipse plugin which will use Hibernate to retrieve and update data, but the jar containing the persistent model classes, xbm and cfg xml files is not know until runtime and so cannot be included in the classpath. I have tried various ways, using a custom classloader to load my classes, but inevitably get a NoClassDefFound exception. While the new classloader can find my classes, Hibernate classes can't find mine.

Any suggestions?

Thanks!
Mike

osgi redefines classloading and thus frameworks relying on standard java classloading will have issues.

Eclipse provides a notion of buddy classloading to solve this exact problem.

Google it and you should find plenty of examples.