Just to confirm above statement:

The page we are trying to display contained in URL is rendered correctly using the render() method. All CSS, images, HTML etc are rendered correctly as per normal. The jsessionid however is not being transferred to the page used in the render() method.

This means that where session values are displayed on the page, the value is showing as blank. This is because a new session is created by default in which our attributes used on the page don’t exist.