I have been unable to find out any details about this specific error message, other than for Google Chrome, which is strange because although I have Chrome installed I don't use it, I use either Internet Explorer or - most often - Firefox. This error is only occurring on the Firefox browser and is not isolated to any specific website (it happens regardless of what website I view, including this page).
I have also sent a query to Sun Microsystems - Java support.
I found this on a customer pc.
I removed an application with a firefox plugin called i5 Alert Button.
After Disabling the plugin in firefox I did not get the error anymore.
During the unistall I saw it removing the bolototoolbar file as well.
Incidentally, I had always wondered why an updated version of that alert button never took over the old i5 button when I downloaded it; immediately upon uninstalling i5, the Missing Child Alert Button (http://www.addthealert.com/) replaced it on the toolbar.
I've got the same problem. I realized a web application that must send a request (a get request). The app works correctly on IE, but in Mozilla Firefox catch an exception (in the method http.send()) like this:
I have been getting this issue and no don't have i5 or bolototoolbar. This started to happen after it updated to 6.0. With this issue also can not close tabs and get a script error when trying to close a tab.