onclick or Onmouseout errors?

[Limozine]

Whenever I visit the page http://www.mahloamerica.com/gb/textile/index.html in IE7, I see no error messages on the taskbar until I hover my mouse over the vertical navigation menu on the left side of the page. Then the error symbol and "Error on page" message appears.

I think the message is related to the "onclick" attributes or the onMouseout attributes, but I'm not sure. After all, many other pages on the same site use the same attributes but don't get any error messages. Any ideas on how to get rid of the error messages?

[Centauri]

It seems to be related to the covr and cout functions :<SCRIPT language=javascript>
<!--
function covr(cell,col){if (!cell.contains(event.fromElement)){cell.style.cursor = 'hand';cell.bgColor = col;}}
function cout(cell,col){if (!cell.contains(event.toElement)){cell.style.cursor = 'default';cell.bgColor = col;}}
function cclk(cell){if(event.srcElement.tagName=='TD'){cell.children.tags('A')[0].click();}}
//-->
</script>The error I see is "event is not defined".

As I am not a javascript person, you may get a better response posting in the Javascript forum.