the use of AM_PATH_PYTHON is not portable enough reverting back to

* configure.in: the use of AM_PATH_PYTHON is not portable enough
  reverting back to AM_PATH_PROG
Daniel
diff --git a/configure.in b/configure.in
index ac3c3ed..cc1950d 100644
--- a/configure.in
+++ b/configure.in
@@ -633,7 +633,7 @@
 	    then
 	        echo Found python in environment PYTHON=$PYTHON
 	    else
-		AM_PATH_PYTHON()
+		AC_PATH_PROG(PYTHON, python python2.6 python2.5 python2.4 python2.3 python2.2 python2.1 python2.0 python1.6 python1.5)
 	    fi
 	fi
     fi