Hi Manoj,
Since it a new Interface, you can create the WSDL in similar way as you did for your 1st Interface.
The Endpoint would look something as follows:
http://server:port/XISOAPAdapter/MessageServlet?
What type of authentication is being used in your scenario. If they need User/ID based authetication, you need to provide them with a valid Pi UserID / Password inorder to connect to PI system.
Regards,
Azhar