The <a4j:portlet> should be used in a portal environment. The main component purpose is implementation of possibility to create several instances for the same portlet on one page.

Portal page can include some instances of the same portlet but clientId of elements should be different for each window. In that case 'namespace' is used for each portlet. The <a4j:portlet> implemets NaimingContainer interface and adds a namespace to all components on a page. All portlet content should be wrapped by <a4j:portlet> for resolving the problems mentioned before.

More info about portal environments support can be found on the users forums.

Portlet Sample could be checked out from JBoss SVN: portal-echo application

Usage instructions for this demo could be found at the corresponding: JBoss forum topic