MockResponse in Testcase with Testrunner

I'm using soapUI 4.5 and I'm experiencing problems with MockReponse. The testcase is working fine from the UI but when I run it using Testrunner I always get "Unable to access the following endpoint(s): http://nn.nn.nnn.nnn:8088/mockcallback_ ... g/callback".

I cannot see any errors in the log files and I even added a wait step wich start up the Mock Response and waits 20 sec before the steps are really started.

I have seen som other posts here regarding this topic but no solution is provided.

Thanks!