[Javascript] Frame borders revisited

[David T. Lovering]

I'd like to be able to do some kinky things when the cursor in a multi-frame document is resting on the border intersection between two frames.  However, I've yet to see a single handler which captures this event, so writing a simple routine seems to be
out of the question.  I've waded through yards of FAQs and Javascript references, and so far no joy.  For now I would be content with changing the cursor icon at that twilight zone where the cursor is at the edge of one frame, and not quite yet inside the
adjacent one.  [Yes, I know how to change the cursor icon, so please don't send me 300 responses on this portion of the issue].

How about it?  How do I detect this transitional event?

-- Dave Lovering