Drupal 5: Decreasing page load times by minifying javascript using jsmin-php

In an effort to decrease page load times I implemented the following code in a Drupal module to minify my javascript using jsmin-php (http://code.google.com/p/jsmin-php/).

<?php
// define module path
$modulePath = drupal_get_path('module','MYMODULE');

// define javascript file
$jsFile = 'MYMODULE.js';

// define minified javascript filename
$jsFileMin = 'MYMODULE_minified.js';

if (is_writable($modulePath . '/' . $jsFileMin)) {
  require_once('jsmin-1.1.1.php');
  $newJS = JSMin::minify(file_get_contents($modulePath . '/' . $jsFile));
  file_put_contents($modulePath . '/' . $jsFileMin, $newJS);
  drupal_add_js($modulePath . '/' . $jsFileMin);
} else {
  // add module javascript
  drupal_add_js($modulePath . '/' . $jsFile);
}
?>