I always see on mailing lists, irc and such forums that people speaks about OSS (Open Sound System), but that's NOT that OSS, if you ever saw a linux (kernel) configurator you may know that if not take a look at these pictures:
So: what are you using that's ALSA's emulation !
as you can see that OSS what is in the kernel only supports a few devices and it's deprecated.
If you want OSS, download it at http://opensound.com
OSS is now available in 3 OSI licenses: BSD, CDDL and GPL!