Hello,

When attempting to add a ContentPanel to an AccordionLayoutContainer, I get the following error:

Code:
java.lang.AssertionError: Method must be called before the widget is rendered
	at com.sencha.gxt.widget.core.client.Component.assertPreRender(Component.java:1197)
	at com.sencha.gxt.widget.core.client.ContentPanel.setCollapsible(ContentPanel.java:543)
	at com.sencha.gxt.widget.core.client.container.AccordionLayoutContainer.onInsert(AccordionLayoutContainer.java:305)
	at com.sencha.gxt.widget.core.client.container.Container.insert(Container.java:400)
	at com.sencha.gxt.widget.core.client.container.InsertResizeContainer.insert(InsertResizeContainer.java:27)
	at com.sencha.gxt.widget.core.client.container.Container.add(Container.java:88)
It seems that when adding a child to an AccordionLayoutContainer, the add method makes sure the child is collapsible, which is apparently only allowed during pre-render. This severely inhibits the ability to add items to an accordion layout container dynamically. Any hints?