Jason and neilo,
What ivanhalen is trying to say is that once you get the dialogue box for input, you cannot select or highlight the text with your mouse.
I, too, can confirm that you cannot one, select the text with the mouse; and two, move the dialogue box.
It does let you type into the box and save it, but you cannot move it or really use the mouse with it all. It is almost if the Javascript popup was created to not accept any mouse input.
Cheers,
Brian