Patch to get nested layouts with Zend_Layout

zend_layout_nested_layouts_patch.diff

diff --git a/Layout.php b/Layout.php
index 46de129..bfd5ded 100644
--- a/Layout.php
+++ b/Layout.php
@@ -29,6 +29,25 @@
  */
 class Zend_Layout
 {
+
+    /**
+     * Current layout name, being rendered
+     * @var string
+     */
+    protected $_current = null;
+
+    /**
+     * Internal stack to control layout nesting
+     * @var array
+     */
+    protected $_stack = array();
+
+    /**
+     * Holds information about layouts and their parents
+     * @var array
+     */
+    protected $_parents = array();
+
     /**
      * Placeholder container for layout variables
      * @var Zend_View_Helper_Placeholder_Container
@@ -756,6 +775,17 @@ class Zend_Layout
     }
 
     /**
+     * Extend current layout with named layout
+     *
+     * @param string $name The name of the layout
+     * @return Zend_Layout
+     */
+    public function extend($name) {
+        $this->_parents[$this->_current] = $name;
+        return $this;
+    }
+
+    /**
      * Render layout
      *
      * Sets internal script path as last path on script path stack, assigns 
@@ -773,9 +803,13 @@ class Zend_Layout
             $name = $this->getLayout();
         }
 
+        $this->_current = $name;
+        $this->_parents[$name] = null;
+        $viewName = $name;
+
         if ($this->inflectorEnabled() && (null !== ($inflector = $this->getInflector())))
         {
-            $name = $this->_inflector->filter(array('script' => $name));
+            $viewName = $this->_inflector->filter(array('script' => $name));
         }
 
         $view = $this->getView();
@@ -790,6 +824,16 @@ class Zend_Layout
             $view->addBasePath($path, $this->_viewBasePrefix);
         }
 
-        return $view->render($name);
+        $content = $view->render($viewName);
+
+        // Decorate with parent layouts if any is registered
+        if ($this->_parents[$name]) {
+            $this->_stack[] = $this->content;
+            $this->content = $content;
+            $content = $this->render($this->_parents[$name]);
+            $this->content = array_pop($this->_stack);
+        }
+
+        return $content;
     }
 }