Index: dhtml_menu.js
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/dhtml_menu/dhtml_menu.js,v
retrieving revision 1.18.2.3
diff -u -p -r1.18.2.3 dhtml_menu.js
--- dhtml_menu.js	5 Nov 2008 12:14:52 -0000	1.18.2.3
+++ dhtml_menu.js	5 Nov 2008 16:25:36 -0000
@@ -25,12 +25,14 @@ Drupal.behaviors.dhtmlMenu = function() 
   $('.collapsed').removeClass('expanded');
 
   // Get cookie
-  var cookie = Drupal.dhtmlMenu.cookieGet();
-  for (var i in cookie) {
-    // If the cookie was not applied to the HTML code yet, do so now.
-    var li = $('#menu-' + cookie[i]).parents('li:first');
-    if ($(li).hasClass('collapsed')) {
-      Drupal.dhtmlMenu.toggleMenu(li);
+  if (!effects.siblings) {
+    var cookie = Drupal.dhtmlMenu.cookieGet();
+    for (var i in cookie) {
+      // If the cookie was not applied to the HTML code yet, do so now.
+      var li = $('#menu-' + cookie[i]).parents('li:first');
+      if ($(li).hasClass('collapsed')) {
+        Drupal.dhtmlMenu.toggleMenu(li);
+      }
     }
   }
 
Index: dhtml_menu.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/dhtml_menu/dhtml_menu.module,v
retrieving revision 1.29.2.2
diff -u -p -r1.29.2.2 dhtml_menu.module
--- dhtml_menu.module	5 Nov 2008 12:14:52 -0000	1.29.2.2
+++ dhtml_menu.module	5 Nov 2008 16:25:36 -0000
@@ -65,6 +65,10 @@ function dhtml_menu_theme_menu_item($lin
   static $cookie;
   if (!isset($cookie)) {
     $cookie = explode(',', @$_COOKIE['dhtml_menu']);
+    // Do not use this feature when keeping only one menu open at a time - the active path will always be open.
+    if (in_array('siblings', variable_get('dhtml_menu_effects', DHTML_MENU_DEFAULT))) {
+      $cookie = array();
+    }
   }
 
   /* When theme('menu_item') is called, the menu tree below it has been