Yes it does, but it has little to do with the server and all to do with your browser/script software I think. I don't know why, but Javascript and Java applets themselves seem to be very unstable. I get that impression because just having Java installed on your computer can make your browser crash if it is executing a script on a site and something's fucked. I fucking hate java, the whole technology blows ass. I have never not had a problem with Java-based applications.
Even the name sucks. "Java". Sounds like a toy for children.
And I'm gonna assume this message box is either Java, DHTML, or something else that is similar.