var xshift = 0;
var yshift = 0;
function move_me(e) 
{
 if(!e) e = window.event;
 x = e.pageX || e.x;
 y = e.pageY || e.y;
 elem = document.getElementById("chatwindow");
 xshift = x-elem.style.left.substring(0,elem.style.left.length-2);
 yshift = y-elem.style.top.substring(0,elem.style.top.length-2);
 document.onmousemove = function(e)
 {
  if(!e) e = window.event;
  var x2 = e.pageX || e.x;
  var y2 = e.pageY || e.y;
  y2 = y2-yshift;
  x2 = x2-xshift;
  elem.style.left = x2 + "px";
  elem.style.top = y2 + "px";
  chatNumber_Char.innerHTML = "Горизонталь: "+x2+" Вертикаль:"+y2;
 }
 document.onmouseup = function()
 {
 document.onmousemove = null;
 }
}

div.onmousedown = function(){
//действия при нажатии

return false
}