[OU] Error message: Browser doesn't understand Javascript properly

[d]

I have been using Opera for several years and am currently running 
9.25 on WinXP SP2 and current on all updates.

I am having trouble with: http://www.chartware.at/

The site loads, but I get an Opera pop-up with: "Browser doesn't 
understand Javascript properly" when I hover over a stock name. I had 
the same problem with 9.24.

When hovering over a stock name, a menu should be displayed. Clicking 
on one of the menu items will cause more detailed information to be displayed.

I have not used this site for a while (several months at least), but 
I know Opera did, at one time, work with the site by displaying the 
(hover) menu and subsequent detail information.

I have Javascript enabled and no site specific alterations. This is 
the only site that has shown this pop-up.

I have tried IE6.0, Firefox 2.0.0.11 and K-meleon 0.9 and all work 
the same by displaying the menu and the subsequent detail information.

Does anyone have suggestions for me to try to get this site working again?

Thanks,
Dwight