I'm only setup to test the official Windows build setup under PCbuild. 
I'm not testing the legacy build setups under PC/VC6, PC/VS7.1, or PC/VS8.0.

The patch against the trunk failed for PC/VC6/pythoncore.dsp.  I don't
need that to build, though.

Your patch built fine, with one warning about a loss of precision on the
following line in sinpi():

    n = round(2.0*y);

I recommend explicitly casting the result of round() to int, to get rid
of the warning and because explicit is better than implicit. :)

I ran the following tests, all of which passed:

PCbuild/python.exe Lib/test/regrtest.py -v test_math

I appreciate your work on this patch.  Let me know if there's anything
else I can do.