os x framework tcl/tk headers

[John Hunter]

I am using distutils on a darwin 10.3 OS X machine to install a
python package which needs to find the tcl/tk headers to compile.  On
my system those headers are located at

  /Library/Frameworks/Tcl.framework/Versions/8.4/Headers/tcl.h
  /Library/Frameworks/Tk.framework/Versions/8.4/Headers/tk.h

For linking, I have found the following helpful

            framework = ['-framework','Tcl', '-framework', 'Tk']
            module.extra_link_args.extend(framework)

Is there an analog to help distutils find the headers, eg, the
equivalent for module.extra_compile_args or module.include_dirs?  I
know I can add them manually for a specific include path.  My question
is: is there a way to use the framework to add the appropriate flags
in a distutils build environment to find these headers automagically?

Thanks!
JDH