[Zope] Peculiar effects with SQL tree

I have a dtml-tree which is getting its tree data from an sql method: <dtml-let oid="0"> <dtml-tree id='oid' branches_expr="sqlSelect_treeParent(parent_id=oid)"> <B><dtml-var name></B> <dtml-var oid> </dtml-tree> </dtml-let> However, with only a small amount of data in the tree table this is behaving in a very strange way, where clicking on expand/collapse links will have random effects, either doing nothing expanding/collapsing a random part of the tree or, occasionall, doing what it should do. Is this a problem anyone else has come across? Cheers, Stephen -- Stephen Harrison - stephen@nipltd.com New Information Paradigms - www.nipltd.com