diff --git a/setup.py b/setup.py
index fd18ade27..21104ec20 100644
--- a/setup.py
+++ b/setup.py
@@ -1,11 +1,11 @@
 import os
+import platform
 import re
 import string
 import struct
 import sys
 
 from distutils.command.build_ext import build_ext
-#from distutils.core import Extension
 from distutils import sysconfig
 from setuptools import Extension, setup
 
@@ -56,6 +56,11 @@ def _find_version(filename):
     return None
 
 
+def _lib_include(root):
+    # map root to (root/lib, root/include)
+    return os.path.join(root, "lib"), os.path.join(root, "include")
+
+
 def _read(file):
     return open(file, 'rb').read()
 
@@ -148,7 +153,7 @@ class pil_build_ext(build_ext):
                     # FIXME: use distutils logging (?)
                     print "--- using Tcl/Tk libraries at", TCL_ROOT
                     print "--- using Tcl/Tk version", TCL_VERSION
-                    TCL_ROOT = libinclude(TCL_ROOT)
+                    TCL_ROOT = _lib_include(TCL_ROOT)
                     break
             else:
                 TCL_ROOT = None