The following is the scenario.
User makes selections on the webpage and clicks on a button, this makes a call to another application sending userId,sessionId in the URL.
the other applicaion now calls a webservice on the first application to get the rest of the user selected information.

I am storing the session information on the first application in a context object and once the call comes into the webservice I get the session object from the context object, create webservice response and send it back.

Please let me know if there is a better way to do this.