Apple has released a new version of its QuickTime multimedia software.
QuickTime 6.3.1 is a supporting release designed for the new version of iTunes. It's a hefty 17.4MB download that is currently available from Apple.
Apple says: "QuickTime 6.3.1 delivers enhanced support for iTunes and other QuickTime-based applications." It requires Mac OS X 10.1.5 or later.