Matthew Kaufman, one of the engineers who brought us RTMFP but who is no longer with Adobe, has written and published an AS3 library which adds support for Apple HTTP Streaming (draft-pantos-http-live-streaming) to OSMF. The classes constitute a plugin for OSMF's HTTPNetStream that supports Apple's m3u8 index files and MP2 transport stream media file.

Matthew outlined his efforts on the FlashMedia List:
"I've put the initial commit of this code up at http://apple-http-osmf.googlecode.com with an open-source license (MPL).

No guarantees that it is complete or optimized, but it does appear to play most of the things I've been able to throw at it. Supports H.264 video and AAC audio... adding MP3 audio support is on the list, just need a sample stream to test with and a couple hours to do it."

Thanks Matthew!