Sharing common code between grails module and java module in same project

We have a multi-module project, the organization of which for simplicity I will describe as

Project
     - java web-service module with Spring and Hibernate facets
     - common java module for code re-use
     - grails application

We have been unable to re-use the common java code module in our grails application.  If we add module dependencies between the grails app and common java module code imports and compiles, but when running the grails application inside of IDEA, the common java module code references are not a part of the classpath and we get groovy "unable to resolve class" compilation failures as if we made some change between building the project and running it. If we call the code indirectly from a groovy class in the src/groovy package it sometimes presents itself as a ClassNotFoundException at runtime.

If we deploy a war built outside of IDEA, it works fine but not being able to run inside of IDEA is making reconsider our choice of grails. Anyone have tips on how this type of organization might work?

thanks,
- Pat Ludwig