redeclare wordpress methods

symfony2-bridge.php

<?php
    /*
    Plugin Name: Symfony2 Bridge
    Plugin URI: http://www.lowpress.com
    Description: Integrate Symfony2 and Wordpress
    Author: Mikee Franklin
    Version: 1.0
    Author URI: http://www.lowpress.com
    */
    
    function rename_template_functions()
    {
      $theme_file = ABSPATH . WPINC.'/theme.php';
      $contents = file_get_contents($theme_file);
      $contents = preg_replace("/function\s+(locate|load)_template(\s*)/", "function \\1_template_old\\2", $contents);
      file_put_contents($theme_file, $contents);
    }

    if (function_exists('locate_template') || function_exists('load_template'))
    {
      rename_template_functions();
    }
    else
    {
      if (!function_exists('locate_template'))
      {
        function locate_template($template_names, $load = false, $require_once = true )
        {

        }
      }
      if (!function_exists('load_template'))
      {
        function load_template( $_template_file, $require_once = true )
        {
	
	}
      }
    
    }