Are you using a WSDL file? Are there 'wsdl:port' elements in there? If so, I think all you would have to do is supply different 'port' parameters (which is confusing to me, because you have no 'port' parameter, and I have them in all of my XML::Compile SOAP code). Or can you add additional ports to the wsdl file, or create 'test' versions of the wsdl file...
Update: I see now...'port' is only required when there are multiple ports defined, and I must be currently using only SOAP api's with multiple ports. Then perhaps an answer for you might be to just create alternate test wsdl files with alternate ports, or multiple ports or something...