using Javascript with an ISMAP tag

[Andy Fish]

Hi,

I would like to get the coordinates as generated by the ISMAP tag (i.e. X
and Y coordinates relative to the corner of the image) but process them in
javascript on the client.

I have seen a couple of other posts about this subject, but it quickly seems
to get into deep levels of browser dependency and coordinate arithmetic
(subtract the border width etc etc).

I would like to support IE, netscape, opera, safari but I don't mind
restricting to recent versions. Is there any of doing this sensibly?

TIA

Andy