Firefox3: Drag-drop does not work across two contenteditable elements

If I have two DIV elements D1 and D2 in a document, both with
contentEditable="true", and I try to drag some text from D1 to D2,
then the text gets removed from D1 (as expected) but does not get
inserted into D2! Is this a known bug? Is there a workaround?

Thanks
Mohan

P.S. While we are at on the subject, is there a built-in property/
method that is equivalent of IE's isContntEditable? I do realize that
I can easily code this by walking up the parent chain until I hit an
element that has contentEditable set to "true" or "false" (as opposed
to the default of "inherit").