Testrunner failing test cases upon parallel execution

Hi folks,

I seem to be having an issue with using the testrunner in SOAPUI free and running certain test cases in parallel.  When I run the same exact test suite in sequence, I have no issues.

This is the error I'm getting upon parallel execution:
javax.wsdl.WSDLException: WSDLException (at /wsdl:definitions/wsdl:types/xsd:schema/xsd:schema): faultCode=OTHER_ERROR: Unable to locate with a locator the schema referenced at 'http://test-test.test.com/schemas/prop/comm/TEST/3.0/valuation.xsd' relative to document base 'http://test-test.test.com/schemas/prop/comm/TEST/calc-agr-valuation/3.0/response.xsd'

What's funny is it only happens for certain test cases (the same ones each time).  I've updated the definition of the WSDL to no avail as well. 

I found some other information about problems with relative schema imports in the forums but it seems here like a relative reference might be happening when it shouldn't.  (( shrug ))

Other info that might help:
- The same project worked prior to SOAPUI 2.5.1. 
- I have the exact same issue in 2.5.1 as 3.0.1
- I am running the test runner from the GUI (right click test suite-> launch testrunner)
- I've experimented with various config settings on the testrunner screen

Unfortunately, I can't send the project file because it contains secure data, so that's out and I realize it'll limit some of what can be found here.

I'm more curious if there's something overarching that I'm missing or some hints and how I could make this work.

Thanks!