[jQuery] setInterval(obj.method,200) problem: scoping?

[Alexandre Plennevaux]

Hello mates,

i have an object datascape which among other things, contains a
property storing the mouse position, and a function that uses that
property. Inside another method i

var datascape = {
   'mouseX': 0,
   'myInterval': 0,
   'create': function(){
       $('#datascape').bind('mousemove', function(e)
        {
            this.mouseX = e.pageX;
        }).bind("mouseover", function()
        {
            this.myInterval = setInterval(this.move, 200);

        }).bind("mouseout", function()
        {
            clearInterval(this.myInterval);
        });
   },

   'move': function(){
          $.log('datascape.move : mouseX = ' + this.mouseX);
        }
}

Yet the script does not work:
firebug console points at the setInterval call, saying:

useless setInterval call (missing quotes around argument?)
http://localhost/prototype/_js/frontend/proto.03.js
Line 172

can someone help me / explain what i'm doing wrong ?

Thank you,

Alexandre

PS: to all jquerians: happy 2009 !!