=== Update ===
Good news! It turns out that the eat/spit components from the [http://qtcomponents.sf.net SourceForge Quicktime Components project] were '''not''' broken by the upgrade to Quicktime 7. It's just the Sound Manager-based
codec component (code 'sdec') that needs to be updated to an AudioCodec. This '''greatly''' reduces the required work, since the AudioCodec API is quite simple compared to the Quicktime component API.
See [http://lists.apple.com/archives/QuickTime-API/2005/Sep/msg00126.html this message] in the quicktime-api mailing list archives for details.