hi, thx for your reply.
I tried your suggestions. The only thing worked was to put the refmap out of mapframe and map DIV. I figured out where the problem is if the refmap is inside the map DIV: In the file zoombox.js there is a function called "doMouseDown". The problem seems to be at last if statement : if (downX < 1 || downY < 1 || downX > refW || downY > refH) { // Don't go ouside of map return false; } else { moveRefBox('shift'); } If the reference map is inside the map div downX and downY are always > refW and refH, so the function always returns false. Andreas