This is what you should do:
// newHeight is a string with units, like "500px"
> We're using a scrollable (scrollable = true; height = 420;) data table
> to present data in a modal dialog window, where it takes up most of
> the window's space. If the user resizes the dialog (eg: to make it
> bigger) I'd like the data table to expand vertically.
> After getting an object handle on the datatable as var dt, which I've
> confirmed works, subsequent lines:
> dt._configs.height = newHeight;
> make the data table expand to full height with a scrollbar that is
> almost the full height (only a few px of scroll).
> There does not seem to be a good way to do this though! Any ideas?