SOAP client for SSO

It is required a simple login implementation using a SSO service through a SOAP service. The pipeline is the following: 1- In a web page I have a Login button. On click, it must be called a SOAP ws using the methods getSAMLRedirectRequestURLWithAssertionConsumerURL or getSAMLPostRequestWithAssertionConsumerURL, and specifying a callback. 2- The web service should open a remote login web page. So, the remote service should call the callback. The callback extracts the parameters and sends them to the ws, through the method verifyResponseWithURL that returns an XML containing authenticated user data or error messages. WS details are the following: Web service: [login to view URL] Namespace: [login to view URL] Trace: 0 I suppose it should be solved crossdomain issues because of AJAX in the first web page.