Shouldn't ever occur... the key code,
Code:
while(true) { Object[] oarr = {o}; o = oarr; }
is not something you're ever going to find in the average applet, even in a harder-to-spot form. I think the author would have to be incredibly unlucky (and a pretty bad coder) or to have crafted the applet specially to cause this effect. It certainly shouldn't happen with any page with an applet on.
It's interesting to note how much attention Sun pay to customer feedback, but I don't think this is related to your problem.
Bookmarks