Web (server) based password manager

I know there have been a few topics here about password managers but I read them all and did not really find what I'm looking for.

What I'd need is a free or cheap (most password mgr software is $500 for 20+ users, exaggerated!) multi-user password manager, highly preferable web-based so that we can host it on one of our local server.

So:
-free or cheap ( <100$)
-multi-user of groups
-web based
-not very hard to install

I tried a few, one very expensive, one I did not get to work-> Web Keepass Manager
This works with tomcat and probably conflicts with our IIS 7.0 or 7.5

PS: thus, nothing online (!) it has to stay local

Thanks in advance!