diff --git a/misc/vertical-tabs.js b/misc/vertical-tabs.js
index 82dcd2c..064b142 100644
--- a/misc/vertical-tabs.js
+++ b/misc/vertical-tabs.js
@@ -38,6 +38,34 @@ Drupal.behaviors.verticalTabs = {
         $(this)
           .removeClass('collapsible collapsed')
           .addClass('vertical-tabs-pane')
+          // Override the default state:visible handler.
+          .bind('state:visible', function(e) {
+            if (e.trigger) {
+              // Get the id of the fieldset.
+              var id = $(e.target).closest('.form-item, .form-submit, .form-wrapper').attr('id');
+              if (id) {
+                // Get the corresponding vertical_tab button.
+                var vertical_tab_button = $('li#vertical-tab-button-' + id);
+                if (vertical_tab_button) {
+                  // Hide or show that instead of the fieldset.
+                  vertical_tab_button[e.value ? 'show' : 'hide']();
+                  // If the vertical_tab_button was currently selected, select
+                  // the one above (or below if there is none above).
+                  if (!e.value && vertical_tab_button.hasClass('selected')) {
+                    var prev_button = vertical_tab_button.prev();
+                    if (prev_button.length != 0) {
+                      prev_button.children().click();
+                    }
+                    else {
+                      vertical_tab_button.next().children().click();
+                    }
+                  }
+                  // Don't bubble this up to the default handler.
+                  return false;
+                }
+              }
+            }
+          })
           .data('verticalTab', vertical_tab);
         if (this.id == focusID) {
           tab_focus = $(this);
@@ -193,7 +221,7 @@ Drupal.verticalTab.prototype = {
  */
 Drupal.theme.prototype.verticalTab = function (settings) {
   var tab = {};
-  tab.item = $('<li class="vertical-tab-button" tabindex="-1"></li>')
+  tab.item = $('<li class="vertical-tab-button" id="vertical-tab-button-' + settings.fieldset.attr('id') + '" tabindex="-1"></li>')
     .append(tab.link = $('<a href="#"></a>')
       .append(tab.title = $('<strong></strong>').text(settings.title))
       .append(tab.summary = $('<span class="summary"></span>')