Problem with Javascript in IE6?

Hey guys i just noticed a problem that im not quite sure about.I was in the middle of designing a website when i attempted to use some rollover buttons in the page.Clicked the test button and IE opens but nothing displays but a blank page.So i something tells me remove the rollover button which is controlled by javascript suddenly it works fine again.Re-add the rollover and javascript issue again.This time i test in Firefox as well and it works fine with the rollover,go back to IE again and blank page.So it seems something with IE isnt working with my javascript code which has worked fine for years.I then tracked down a different version of the javascript through google which resulted in the same problem.

So now i am kinda stumped it's obviously an IE issue but the question is what could be causing this out of the blue?I am using IE6.0.2900.2180 sp2.

Have you tried Java