diff --git a/ndiff/setup.py b/ndiff/setup.py
index e06e87701..58b97c970 100644
--- a/ndiff/setup.py
+++ b/ndiff/setup.py
@@ -1,12 +1,51 @@
 #!/usr/bin/env python
 
+import errno
+import sys
+import os
+import os.path
+import re
+
 import distutils.command
 import distutils.command.install
 import distutils.core
 import distutils.cmd
 import distutils.errors
+from distutils.command.install import install
+
+APP_NAME = "ndiff"
+
+def path_strip_prefix(path, prefix):
+    """Return path stripped of its directory prefix if it starts with prefix,
+    otherwise return path unmodified. This only works correctly with Unix
+    paths; for example it will not replace the drive letter on a Windows path.
+    Examples:
+    >>> path_strip_prefix('/tmp/destdir/usr/bin', '/tmp/destdir')
+    '/usr/bin'
+    >>> path_strip_prefix('/tmp/../tmp/destdir/usr/bin', '/tmp///destdir')
+    '/usr/bin'
+    >>> path_strip_prefix('/etc', '/tmp/destdir')
+    '/etc'
+    >>> path_strip_prefix('/etc', '/')
+    '/etc'
+    >>> path_strip_prefix('/etc', '')
+    '/etc'
+    """
+    absolute = os.path.isabs(path)
+    path = os.path.normpath(path)
+    prefix = os.path.normpath(prefix)
+    if path.startswith(prefix) and prefix != os.sep:
+        path = path[len(prefix):]
+    # Absolute paths must remain absolute and relative paths must remain
+    # relative.
+    assert os.path.isabs(path) == absolute
+    return path
 
 
+
+###############################################################################
+# Distutils subclasses
+       
 class null_command(distutils.cmd.Command):
     """This is a dummy distutils command that does nothing. We use it to
     replace the install_egg_info and avoid installing a .egg-info file, because
@@ -26,6 +65,7 @@ class checked_install(distutils.command.install.install):
     caused by not having the python-dev package installed. By default,
     distutils gives a misleading error message: "invalid Python installation."
     """
+
     def finalize_options(self):
         try:
             distutils.command.install.install.finalize_options(self)
@@ -33,6 +73,43 @@ class checked_install(distutils.command.install.install):
             raise distutils.errors.DistutilsPlatformError(str(e) + """
 Installing your distribution's python-dev package may solve this problem.""")
 
+    def set_modules_path(self):
+        app_file_name = os.path.join(self.install_scripts, APP_NAME)
+        # Find where the modules are installed. distutils will put them in
+        # self.install_lib, but that path can contain the root (DESTDIR), so we
+        # must strip it off if necessary.
+        modules_dir = self.install_lib
+        if self.root is not None:
+            modules_dir = path_strip_prefix(modules_dir, self.root)
+
+        app_file = open(app_file_name, "r")
+        lines = app_file.readlines()
+        app_file.close()
+            
+        for i in range(len(lines)):
+            if re.match(r'^INSTALL_LIB =', lines[i]):
+                lines[i] = "INSTALL_LIB = %s\n" % repr(modules_dir)
+                break
+        else:
+            raise ValueError(
+                        "INSTALL_LIB replacement not found in %s" % app_file_name)
+                    
+        app_file = open(app_file_name, "w")
+        app_file.writelines(lines)
+        app_file.close()
+
+
+    def run(self):
+        install.run(self)
+
+# These below are from Zenmap. We're only using set_modules_path right now, but we might consider whether the others would be useful (or, if not, whether we should remove them from Zenmap).
+#        self.set_perms()
+        self.set_modules_path()
+#        self.fix_paths()
+#        self.create_uninstaller()
+#        self.write_installed_files()
+
+
 distutils.core.setup(name=u"ndiff", scripts=[u"scripts/ndiff"],
     py_modules=[u"ndiff"],
     data_files=[(u"share/man/man1", [u"docs/ndiff.1"])],