Heroku PHP does NOT support MongoDB

This is a personal experience. As of 14th Oct 2011, Heroku PHP does not support MongoDB.

You might expect it to just work, since MongoHQ is listed as an add-on in Heroku.

However, when I use Mongo php class, it gave me a fatal error "Mongo class not found".

I contacted Heroku support, and this is verified - their PHP instance still do not support MongoDB.

Duh.. that's pretty dumb. Looks like Heroku support for it's new languages is still lagging.