It seems indeed like SharePoint is mangling the interaction state by appending the navigational state to it. This seems like something you might want to see with Microsoft as no WSRP producer can deal with modified interaction state (which is supposed to be treated opaquely by the consumer). Another point, it seems as if your portlet is sending complete markup (i.e. a complete xhtml document) as opposed to a fragment as mandated by the specification. This might cause issues with portals as portlets are only expected to generate markup fragments to be aggregated in a complete page. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4209133#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...