Keep TreeNode contents persistent?

[Filip Balas <fb...@IMVProjects.com>]

I am using the Contrib.Tree component.
I have created a custom TreeNode, lets
call it CarTreeNode.

All of my Car objects are cayenne persisted.
When I initialize the tree the first time, the 
page loads and I have verified throught the debugger
that all of my Car objects are correctly inserted
into the data model.

However, everytime I click on a node and enter
the 'treeStateChanged' method, all of the nodes
have lost their reference to thier corresponding
Car objects?  The tree still manages to continue
rendering (even though the underlying object it
gets its value from is gone).  How can I get Tapestry/
Tree component to persist the internals of my TreeNode?

Filip