Can't run groovy test steps imported from soapUI pro

Hey, I've been getting a java.lang:NoClassDefFoundError all day, and haven't been able to trace this darned thing down. A bit of background. I have a groovy script in my soapui project that uses a handful of external jars. They're all in my ext folder of soapui and the script runs fine. The problem is, once I import this script (in its containing test suite) i get the NoClassDefFoundError. Now, i've copied my ext folder from soapui over to loadui, so i'm not sure why there is still problems finding these external dependencies.

Any thoughts?

Thanks,

Dan