Why don't you initialize your listener, including a boolean value. Initially as you say, the mouse will be 0,0. So while it's in that position, the value is false, so don't add your follower. When it stops being 0,0 - change the boolean value to true - and thus your follower will be added.
Other than that, paul is speaking sense. I presume your problem is that your follower is stuck at 0,0 and looks silly until the mouse has actually moved.
You could also check the position of the mouse vs the extremeties of the window, and if they match, remove the follower (or preferably set the cullhint to avoid continually adding and removing a simple node.
Does that help?