Using @PYTHON@ for this path would result in the build system python being 
referred to. Instead we want to locate python from the environment.

Upstream Status: Inappropriate [configuration]

diff -ruN libglade-2.6.4-orig//libglade-convert.in libglade-2.6.4/libglade-convert.in
--- libglade-2.6.4-orig//libglade-convert.in	2011-09-22 10:18:28.991164003 +0800
+++ libglade-2.6.4/libglade-convert.in	2011-09-22 10:18:55.431164003 +0800
@@ -1,4 +1,4 @@
-#!@PYTHON@
+#!/usr/bin/env python
 # -*- mode: python -*-
 
 # yes, this requires python 2.x and an XML parser module (eg. PyExpat)