diff --git a/CHANGELOG b/CHANGELOG
index 2e8665808..fc4d559e3 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,12 @@
 # Nmap Changelog ($Id$); -*-text-*-
 
+o [Ndiff] The setup.py installation script now suggests installing the
+  python-dev package in a certain error situation. Previously the
+  error message it printed was misleading:
+    error: invalid Python installation: unable to open
+    /usr/lib/python2.6/config/Makefile (No such file or directory)
+  The change was suggested by Aaron Leininger. [David]
+
 o Ncat's HTTP proxy now supports the GET, HEAD, and POST methods in
   addition to the CONNECT tunneling method, so it can be used as a
   proxy with an ordinary web browser. [David]
diff --git a/ndiff/setup.py b/ndiff/setup.py
index 49a584adb..f128ac69f 100644
--- a/ndiff/setup.py
+++ b/ndiff/setup.py
@@ -1,9 +1,12 @@
 #!/usr/bin/env python
 
-from distutils.core import setup
-from distutils.cmd import Command
+import distutils.command
+import distutils.command.install
+import distutils.core
+import distutils.cmd
+import distutils.errors
 
-class null_command(Command):
+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 there's
     no option to disable that."""
@@ -14,6 +17,17 @@ class null_command(Command):
     def run(self):
         pass
 
-setup(name = u"ndiff", scripts = [u"ndiff"],
-      data_files = [(u"share/man/man1", [u"docs/ndiff.1"])],
-      cmdclass = {"install_egg_info": null_command})
+class checked_install(distutils.command.install.install):
+    """This is a wrapper around the install command that checks for an error
+    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)
+        except distutils.errors.DistutilsPlatformError, e:
+            raise distutils.errors.DistutilsPlatformError(str(e) + "\n"
+                + "Installing your distribution's python-dev package may solve this problem.")
+
+distutils.core.setup(name = u"ndiff", scripts = [u"ndiff"],
+    data_files = [(u"share/man/man1", [u"docs/ndiff.1"])],
+    cmdclass = {"install_egg_info": null_command, "install": checked_install})