A configurable HTML editor, like TinyMCE or FCKEdit or maybe something simpler as long as I can configure it to have those character tags I need (em, strong, sub/superscript, maybe a few others).
As I see it the dataInit function passes you the element but it isn't in context.. therefore you can edit the element (change attributes of the element, callbacks, etc.. of in this case the textarea) but you can't change what the element is.
I know afterCellEdit is supposed to be after the tag is in place, but when I print the html of the cell during the callback it shows no textarea.. just what was there to start.