hmm, illegal operation? were u visiting some (Illegal) sites? hahaha, kidding., sorry for that.
the sites u've opened mu have Java into it, and that code must be corrupted. this isnt anything to worry about. as brower's function is to execute HTML rather than embeded things which are executed from third party tools, like Java by java virtual machine, quick time = quick time player, real media = real player, flash sites = shockwave player etc.
hope it made u clear of the things, did it?