multiple projects with same port

Hello,
I created multiple SoapUI Mockup Projects. If the port of each mockup service is unique and not already used by an other project, everything ist working fine.
The path is usually the same of all project but it's not always the case because of legacy code.
Is it possible to configure all the projects with the same port? I already tried it, but I got an exception...

Missing operation for soapAction [] and body element [null] with SOAP Version [SOAP 1.1]

Maybe I'm doing something wrong?

SoapUi version 4.0.1

Thanks in advance,
Jack