diff --git a/preprocessed/pp.py b/preprocessed/pp.py
index ebd7b41..c79b63b 100644
--- a/preprocessed/pp.py
+++ b/preprocessed/pp.py
@@ -247,9 +247,10 @@ class pretty:
         self.output.write(line)
         self.prev_line = line
 
-def main():
-    p = pretty(os.path.basename(sys.argv[2]))
-    for line in fileinput.input(sys.argv[1]):
+def main( src, dest ):
+    p = pretty( os.path.basename( dest ) )
+    for line in fileinput.input( src ):
         p.process(line)
 
-main()
+if __name__ == '__main__':    
+    main( sys.argv[1], sys.argv[2] )
diff --git a/preprocessed/preprocess.cmd b/preprocessed/preprocess.cmd
index fed63ba..d1042c3 100755
--- a/preprocessed/preprocess.cmd
+++ b/preprocessed/preprocess.cmd
@@ -1 +1 @@
-gcc -E -C -P -I%1 "-D BOOST_USER_CONFIG=<%1/libs/mpl/preprocessed/include/%2/user.hpp>" -D BOOST_MPL_CFG_NO_OWN_PP_PRIMITIVES %3 >%4
+gcc -E -C -P "-I%(boost_root)s" "-D BOOST_USER_CONFIG=<%(boost_root)s/libs/mpl/preprocessed/include/%(mode)s/user.hpp>" -D BOOST_MPL_CFG_NO_OWN_PP_PRIMITIVES %(file)s >"%(file_path)s"
diff --git a/preprocessed/preprocess.py b/preprocessed/preprocess.py
index 1794041..d5c7c24 100644
--- a/preprocessed/preprocess.py
+++ b/preprocessed/preprocess.py
@@ -11,17 +11,26 @@
 # $Date$
 # $Revision$
 
+import pp
 import shutil
 import os.path
 import os
+import string
 import sys
 
+preprocess_cmd = open( "preprocess.cmd" ).readlines()[0]
+
 def process( file, boost_root, dst_dir, mode ):
     file_path = "%s.hpp" % os.path.splitext( file )[0]
+    os.system( preprocess_cmd % {
+          'boost_root': boost_root
+        , 'mode': mode
+        , 'file': file
+        , 'file_path': file_path
+        } )
 
-    os.system( "preprocess %s %s %s %s" % ( boost_root, mode, file, file_path ) )
     os.rename( file_path, "%s.tmp" % file_path )
-    os.system( "python pp.py %s.tmp %s" % ( file_path, file_path ) )
+    pp.main( "%s.tmp" % file_path, file_path )
     os.remove( "%s.tmp" % file_path )
 
     filename = os.path.basename(file_path)
@@ -75,5 +84,5 @@ if __name__ == '__main__':
     main(
           ["bcc", "bcc551", "gcc", "msvc60", "msvc70", "mwcw", "dmc", "no_ctps", "no_ttp", "plain"]
         , "src"
-        , "boost\\mpl\\aux_\\preprocessed"
+        , os.path.join( "boost", "mpl", "aux_", "preprocessed" )
         )