import distutils.core
import numpy.distutils.misc_util

distutils.core.setup(name = 'ar',
    url = 'http://rhysu.github.com/ar/',
    ext_modules = [
        distutils.core.Extension(
            'ar',
            sources = ['ar-python.cpp'])
    ],
    include_dirs = numpy.distutils.misc_util.get_numpy_include_dirs()
)

@@ -192,24 +192,58 @@
       'ar',%0A
+            depends = %5B'ar.hpp'%5D,%0A
             
@@ -269,16 +269,25 @@
 on.cpp'%5D
+%0A        
 )%0A    %5D,

Add ar.hpp dependency to setup.py