Q:

Spring mvc app and php forum and wiki integration

I've got web application developed in spring mvc, java, mysql (hibernate).  Now the customer wants new features.  Forum and wiki.  
From past experience I know of two good ones but they're done in php, those are either phpbb/mybb/punbb or mediawiki for wiki. 
Since I have secure salted password in my database with custom salting methods, I was wondering what would be good way of integrating those two or those three working together? 
By working together I mean when user logs in the spring mvc app, he shouldn't re-login in order to appear logged in once on forum or wiki. 
Right now I have no idea where to start let alone how to do it, some creative ideas would be excellent from whoever people with or without experience with these. 

A:

The canonical answer to this is to set up an OpenID infrastructure (based on your Spring MVC web app with its password store) and use OpenID integration to authenticate users on the forum and wiki apps.  
There's an OpenID plugin for phpbb; MediaWiki also has a plugin.  
You can learn about OpenID from the interwebs; here's an article on using OpenID with Spring Security. 