I've written some preliminary patches to support via tech 8233 on-board
ac97 audio.  I need to work out a few more things (ac97 stuff needs to
be updated, or else I need to revert this to the old rate setting
behavior).  Anyway, if anyone else has such a beast and would like to
try out the patches (audio works quite well for me), the patches are at:

http://cryptonomicon.org/~jolan/files/netbsd/

- jolan