Apple Safari is working

Finally we found the JavaScript problem that prevented Apple Safari users to switch between the diagrams. The diagram select box was always disabled. The problem was caused by the event handlers onmousedown and onmouseup that where set for the whole document. The problem disappeared after we have registered our handlers on the appropriate div alone. It seems unlikely that this behaviour is intended by Apple so we think that it is some sort of bug in Apple Safari.

Addon: we reported the problem and found out that our mouse handlers did not return valid return codes in all cases. Our mistake of course, but we recommend that this situation should be handled more fault tolerant by Safari.