CAPI question: expanding and collapsing custom nodes

Hi

I have a graph-pane with :node-pane-function returning a SIMPLE-PANE 
(i.e. not a subclass of EXPANDABLE-ITEM-PINBOARD-OBJECT)

How can I make such nodes expand and collapse?

As a second question: can I make a simple-pane class inherit from 
EXPANDABLE-ITEM-PINBOARD-OBJECT?

Thanks

--
Marco Antoniotti					http://bioinformatics.nyu.edu/~marcoxa
NYU Courant Bioinformatics Group		tel. +1 - 212 - 998 3488
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