simpleTogglePanel inside tabPanel does not collapse on FireF

[mores]

IE:
When simpleTogglePanel is expanded the tabPanel is expanded.
When simpleTogglePanel is collapsed the tabPanel is collapsed.

FireFox:
When simpleTogglePanel is expanded the tabPanel is expanded.
When simpleTogglePanel is collapsed the tabPanel does not collapse !

Resizing the window, or selecting another tab makes the tabPanel collapse.

Is there a workaround for this or should I enter it as a bug ?

I am seeing this on 3.1.4-GA, 3.2.0-GA, 3.2.1-SR1

<rich:tabPanel switchType="client">
 <rich:tab label="First">
 <rich:simpleTogglePanel switchType="client" label="Client Switch Type" opened="false">
 <ol>
 <li>Apples</li>
 <li>Oranges</li>
 <li>Bannanas</li>
 <li>Grapes</li>
 <li>Lettuce</li>
 <li>Tomatoes</li>
 <li>Bread</li>
 <li>Milk</li>
 <li>Ham</li>
 </ol>
 </rich:simpleTogglePanel>
 </rich:tab>
 <rich:tab label="Second">
 Here is tab #2
 </rich:tab>
 </rich:tabPanel>