For what it's worth, I've been using a patch nearly identical to this one with python 2.6.x and 2.7.x with good success, and in my case it was under Solaris 10 with the no-cost "oss" package from 4Front.  I now have a new workstation and I've installed OpenIndiana (one of the OpenSolaris derivatives) on it, so I've had to revisit my patch slightly to get it to work with Python 2.7.5.

It causes no real harm to attempt to build ossaudiodev even on earlier Solaris platforms that don't have the package installed.  With Brian's patch or mine, the build reports that it expected to build ossaudiodev but that build failed.  There are other modules that setup.py expects to have work on Solaris that do not, so this is not the first instance of trying something only to have it gracefully fail.  It's really no different from what's being done with linux -- setup.py attempts to build ossaudiodev for all Linux distributions, even though some of them have ripped out support for OSS, in favor of ALSA or Pulse.

I would agree that using individual ifdef's for each define is useful; it appears that the oss package from 4Front provides more of the defines than the modified "Boomer" OSS headers that are part of the OpenSolaris derivatives.

My recommendation would be that Brian's patch or something like it be included as a bug fix in any releases of Python, not as just a "new feature" in the latest release.