Index: javascript_aggregator.module
===================================================================
--- javascript_aggregator.module	(revision 477)
+++ javascript_aggregator.module	(working copy)
@@ -47,7 +47,7 @@
     }
 
     // Generate a unique filename from the set of JavaScript files.
-    $filename = md5(serialize($scripts_js_files)) .'.js';
+    $filename = md5(serialize($scripts_js_files) . variable_get('javascript_aggregator_version_number', 0)) .'.js';
 
     // Create files/js similar to drupal_build_css_cache (common.inc).
     $jspath = file_create_path('js');
@@ -160,6 +160,16 @@
       '#description' => t("This option can interfere with module development. It is recommended to only turn this on when your site is complete."),
     );
 
+    $form['javascript_aggregation']['javascript_aggregator_version_number'] = array(
+      '#type' => 'textfield',
+      '#title' => t('Cache File Version Number'),
+      '#default_value' => variable_get('javascript_aggregator_version_number', 0),
+      '#disabled' => !$is_writable,
+      '#size' => 20,
+      '#maxlength' => 20,
+      '#description' => t("Change this number if your aggregated scripts have changed to invalidate the user's browser cache."),
+    );
+
     $form['javascript_aggregation']['javascript_aggregator_jsmin'] = array(
       '#type' => 'checkbox',
       '#title' => t('Minify with JSMin'),