I have questions about how to create a link from a portal to another one.

For example: I have a war(which include a xxx-Object.xml) to show a Product List.  When click the product item in product list page, the product detail page will display. 

Now I have another war(include another ***-Object.xml) to show Home. There is also a Product List portlet in it. Maybe a Recommended Product List, What I want to implement is when click the product item in the recommended product list, the product detail page in the first war will show.

I use portlet bridge and JSF/Seam in my project.

How to do this?     Thanks!