WSIFException

Hi     
      My application  has to call a  .Net webservice . It is working fine
      when  I called through a client(using dynamic WSIF) on my machine(Windows)  that  is not behind the firewall
      But when I put it on the Unix box that  is behind the firewall I got the exception(Unable to find an available port)     
      It seems a firewall issue but I am not sure. 
      Earlier I was unable to  invoke the URL  on which webservice is running, but later they(firewall)
      open a port 443 for outbound request to invoke this URL which is working fine now 
      But still I am getting follwing exception

      org.apache.wsif.WSIFException: Port 'CWESPSoap' is not available and  no alternative can be found
 
      Here  is the code also
      
                      WSIFService service =  factory.getService(wsdlLocation,   null,   null, portNameSpace, servicePort);      
                      java.util.Iterator it = service.getAvailablePortNames();
 
                     while (it.hasNext()) {
                         System.out.println("port");
                          System.out.println(it.next());
                       }
 
                  // get the port
                  WSIFPort port = service.getPort("CWESPSoap");    at // 1
 
                got exception as mention above . Also tried using default port  then exception message is Unable to find an available port
              I am woking through ssh on unix box
 
Please help me .
 
Regards & Thanks
Sachin