Oracle is now charging $90 for the free Sun plug-in that teaches Microsoft Office how to use the latest open document format.

As noticed by The H, if you visit the home of the Sun ODF Plugin for Microsoft Office, there's still a big red button that says you can "Get it Now. Free." But if you actually click on that button, Oracle says you can't get it now unless you fork over $9,000. That's $90 per user, with a minimum of 100 users.

Oracle is also offering support for the not-so-free plug-in. That'll cost you $19.80 per user for the first year - aka a minium of $1,980 - but you don't have to pay this if you don't feel like it.

You do have to pay the $9,000.

The latest version of the Sun PDF Plugin teaches Microsoft Office how to read, edit, and save in ODF 1.2, the version used by OpenOffice 3.2. Redmond introduced ODF with Microsoft Office 2007 Service Pack 2, but the best it can do is ODF 1.0. The plug-in also plugs into Microsoft Office 2003, XP, and Microsoft Office 2000.

The plug-in was never open source. It was just free. So, Oracle isn't reversing an open source promise. But it is charging $90 for a plug-in. The Home and Student edition of Microsoft Office 2007 costs $149.95, and the standard edition is $399.94. So, even if we're kind, the cost of four plug-ins buys you the entire suite. ®