look here:

first image: the whole image is an image map - onmouseover call a javascript popup window

this one works in all browsers!

second image: only the inner rectangle (questionmark) is defined as image map - should display popup as with the first image

with all browsers I testet (IE,NN4.6,Phoenix0.5) this works but it does not work with Mozilla 1.3b (build: 20030120)

can anyone help?
if you don't know how to solve it, can you please test with your mozilla and report if it works