It seems a little mistakes around the menu module yet...
I tried to install each mambot which you recommended above, but they both made the menu working wrong: when I try to direct (hover) mouse on buttons, buttons just getting disappeared! Take a look here:
www.polygon.cre-active.eu - there is fixed version of FishEye menu (according your advices in this topic) and PNG corrector mambot.
Another kind of problem is errors with Javascript (browser IE6 wrote about these errors in the bottom) when I load the page first time, if I refresh the page all is okay. It's because I inserted this line:
<script type="text/javascript" src="modules/fisheye_menu/pngfix.js"></script>
in the template. If I remove this link from the template, the problem is gone.
Look forward to yours reply,
Eugene.