diff --git a/framework/yii/console/controllers/HelpController.php b/framework/yii/console/controllers/HelpController.php
index c40ea66..a729f78 100644
--- a/framework/yii/console/controllers/HelpController.php
+++ b/framework/yii/console/controllers/HelpController.php
@@ -13,7 +13,7 @@ use yii\base\InlineAction;
 use yii\console\Controller;
 use yii\console\Exception;
 use yii\console\Request;
-use yii\helpers\StringHelper;
+use yii\helpers\Inflector;
 
 /**
  * This command provides help information about console commands.
@@ -96,7 +96,7 @@ class HelpController extends Controller
 		foreach ($class->getMethods() as $method) {
 			$name = $method->getName();
 			if ($method->isPublic() && !$method->isStatic() && strpos($name, 'action') === 0 && $name !== 'actions') {
-				$actions[] = StringHelper::camel2id(substr($name, 6));
+				$actions[] = Inflector::camel2id(substr($name, 6));
 			}
 		}
 		sort($actions);
diff --git a/framework/yii/jui/Accordion.php b/framework/yii/jui/Accordion.php
new file mode 100644
index 0000000..df9ba20
--- /dev/null
+++ b/framework/yii/jui/Accordion.php
@@ -0,0 +1,107 @@
+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\jui;
+
+use yii\base\InvalidConfigException;
+use yii\helpers\base\ArrayHelper;
+use yii\helpers\Html;
+
+/**
+ * Accordion renders an accordion jQuery UI widget.
+ *
+ * For example:
+ *
+ * ```php
+ * echo Accordion::widget(array(
+ *     'items' => array(
+ *         'Section 1' => array(
+ *             'content' => 'Mauris mauris ante, blandit et, ultrices a, suscipit eget...',
+ *             'contentOptions' => array(...),
+ *         ),
+ *         'Section 2' => array(
+ *             'content' => 'Sed non urna. Phasellus eu ligula. Vestibulum sit amet purus...',
+ *             'headerOptions' => array(...),
+ *         ),
+ *     ),
+ * ));
+ * ```
+ *
+ * @see http://api.jqueryui.com/accordion/
+ * @author Alexander Kochetov <creocoder@gmail.com>
+ * @since 2.0
+ */
+class Accordion extends Widget
+{
+	/**
+	 * @var array list of sections in the accordion widget. Each array element represents a single
+	 * section with the following structure:
+	 *
+	 * ```php
+	 * // item key is the actual section header
+	 * 'Section' => array(
+	 *     // required, the content (HTML) of the section
+	 *     'content' => 'Mauris mauris ante, blandit et, ultrices a, suscipit eget...',
+	 *     // optional the HTML attributes of the content section
+	 *     'contentOptions'=> array(...),
+	 *     // optional the HTML attributes of the header section
+	 *     'headerOptions'=> array(...),
+	 * )
+	 * ```
+	 */
+	public $items = array();
+
+
+	/**
+	 * Renders the widget.
+	 */
+	public function run()
+	{
+		echo Html::beginTag('div', $this->options) . "\n";
+		echo $this->renderItems() . "\n";
+		echo Html::endTag('div') . "\n";
+		$this->registerWidget('accordion');
+	}
+
+	/**
+	 * Renders collapsible items as specified on [[items]].
+	 * @return string the rendering result.
+	 */
+	public function renderItems()
+	{
+		$items = array();
+		foreach ($this->items as $header => $item) {
+			$items[] = $this->renderItem($header, $item);
+		}
+
+		return implode("\n", $items);
+	}
+
+	/**
+	 * Renders a single collapsible item section.
+	 * @param string $header a label of the item section [[items]].
+	 * @param array $item a single item from [[items]].
+	 * @return string the rendering result.
+	 * @throws InvalidConfigException.
+	 */
+	public function renderItem($header, $item)
+	{
+		if (isset($item['content'])) {
+			$contentOptions = ArrayHelper::getValue($item, 'contentOptions', array());
+			$content = Html::tag('div', $item['content']) . "\n";
+		} else {
+			throw new InvalidConfigException("The 'content' option is required.");
+		}
+
+		$group = array();
+		$headerOptions = ArrayHelper::getValue($item, 'headerOptions', array());
+		$group[] = Html::tag('h3', $header, $headerOptions);
+		$group[] = Html::tag('div', $content, $contentOptions);
+
+		return implode("\n", $group);
+	}
+}