Intranet portals

Some company (multinational, ~200 employees) got smart and decided not to throw $20000+ for an intranet portal they can get for almost free. So instead of using something like Oracle Portals and Java stuff (waste of time and money), they want me to adapt a PHP (productivity, horizontal scalability) portal for their purposes.

Requirements are Oracle DB (I'll have to convert MySQL calls to Oracle if it doesn't have native support for it), integration with an LDAP directory (at least for authentication), and a good calendar software. I'm to take care of the rest, like the particular mods required by this company on the calendar,  ensuring the boards are up to the PHPBB2 standards, etc. A nice plus would be support for managing external documents (PDF, DOC) uploaded to the portal and not just written in it, and the ability to index and search such documents.

I've been evaluating many portals/CMSs, including PHP-Nuke (which I've used in the past), PostNuke, XOOPS, MDPro, Mambo, TikiWiki, and ezPublish. For now MDPro looks best but I wanted to know if you have any advice on this or you know of a portal that better fits my needs.

Anonymous VIPper will be thankful ^_^.

[b][i][o]I AM A HIGH-LEVEL CLERIC AND THIS UNDEAD THREAD TURNS IN MY PRESENCE.[/b][/i][/o]