Sometimes "Missing operation for soapAction"

Hi,

I have created a mock service and I have the following strange behaviour:

1. Open SoapUI
2. Start MockService
3. Run a test case/test request against the MockService (works great!)
4. Run the test case/test request again (does not work!!!)
=> I get "Missing operation for soapAction"
=> Very strange since it worked the first time (I promise nothing has been changed from the first time)
5. Wait for a couple of minutes (works again!)
6. Run the test case/test request again (does not work!!!)
=> I get "Missing operation for soapAction"
=> Very strange since it worked the first time

Has anyone experienced the same problem? Is there a solution/workaround for this?

BR,
Anders