JythonContainerBuilder does not work within Maven Tests

The following lines from JythongContainerBuilder throw an error when executed from within Maven.

            interpreter.exec("from org.nanocontainer import *");
            interpreter.exec("from org.nanocontainer.reflection import *");
            interpreter.exec("from java.net import *");

The Jython interpreter complains about no known module nanocontainer. It runs great within Eclipse, so I have to assume there's some issue with Jython + Surefire.