Forum OpenACS Development: TableWidget - is date sort by hidden field possible

I'm using the TableWidget in a portlet and wish to display a date field in a dd-mm format but have the sort work on a yy-mm-dd format.

Is it possible to sort by (an effectively) hidden field?

There's a workaround possible by including an index counter when building the list and then using that to sort, but doesn't feel the most elegant solution...

cheers
Matthew