This sounds really neat.  but as Anotine said it'll be several weeks 
before any of us can give this serious attention.  Definitely update to 
trunk and base your work off of that.

quick comments:

Your _sre.c diff appears to remove and replace the entire file.  I don't 
think thats actually what you did.  Chances are that diff is a result of 
changed newline f lea.  Can you please make sure your file uses the 
previous line ending style so that the diff is more managable.

Also, please include unit test updates to validate all new functionality 
in Lib/test/test_re.py.

thanks for your efforts!  -gps