One of the most common questions we see in these forums is how to have two portlets that are packaged in different war files, communicate with each other. For the most part, the APPLICATION_SCOPE of the PortletSession is the best answer when we have portlets packaged within a common application, but when they are packaged in separate war files, a new solution must be use.
IBM's WebSphere portal provides a technology called Click-to-Action, or C2A to achieve this. Is there a similar technology supplied by Liferay that makes inter-portlet communication easier than generating a home-grown solution?
subject: Interportlet Communication with Liferay for Separately Packaged Portlet Applications