Clean URL checking buggy

I checked out Drupal HEAD (checked out 1746 - 400 -- or 5:46 PM EDT ) on 8/19. I am running it on Apache 2.2.4 / MySQL 5.0.45 and PHP 5.2.3 on Windows Vista (booooo!). When I enable Clean URLs during the install, all of the Clean URL-style links fail. When I turn Clean URLs off, navigation works as it should.