Adding Nested Menus in SharePoint 2010

Adding nested menus in SharePoint 2010.
You can build your own web controls using the ControlAssembly and ControlClass properties, and thereby create hierarchical menu structures. The steps in this process are as follows:

1. Create a web control which is rendered in the style of the MenuItemTemplate class
2. Register it as safe in the web.config file
3. Create a custom action in the elements.xml file of the feature which has a reference to a web control
4. Add custom actions as menu items