So from my understanding this is a simple PHP page not a SOAP service. Remember XML is just the protocol used in a SOAP service however a SOAP service consists out of a WSDL that is published describing operations and how to call those operations.
A simple PHP page even if it returns XML data is NOT a SOAP service and thus does NOT have a WSDL. You wont be able to use WSDL2JAVA for that.
This PHP page seems more like a REST type service that returns XML instead of JSON. To be honest it really sounds like a REST service.
Try using the latest SOAPUI to connect to the page and see if you can use the REST project type with this page. If it is a REST service it might have a WADL file. YOu can use the WADL2JAVA cxf utility to generate classes to you. HOwever this is a BIG might as most REST services dont use WADL's yet. See this link on CXF