function Browser() {

  var browserUserAgent, browserUserAgentName, browserUserAgentNamePosition;

	// Set Default browser to behave like Netscape
	// used 2 variables for future enhancements if required.
  this.isInternetExplorer = false;
  this.isNetscape = true;

  browserUserAgent = navigator.userAgent;

  browserUserAgentName = "MSIE";
  if ((browserUserAgentNamePosition = browserUserAgent.indexOf(browserUserAgentName)) >= 0) {
    this.isInternetExplorer = true;
    this.isNetscape = false;
    return;
  }
}

// variables to hold moving object information
var browserObject = new Browser();
var movingObject = new Object();
//movingObject.zIndex = 0;

function OnStartMovingObject(event, id) {

  var x, y;
  
  // get moving object    
  movingObject.elementNode = document.getElementById(id);

  // Get cursor position with respect to the page.
  if (browserObject.isInternetExplorer) {
    x = window.event.clientX + document.documentElement.scrollLeft
      + document.body.scrollLeft;
    y = window.event.clientY + document.documentElement.scrollTop
      + document.body.scrollTop;
  }
  if (browserObject.isNetscape) {
    x = event.clientX + window.scrollX;
    y = event.clientY + window.scrollY;
  }

  // Saving positions of element and cursor.
  movingObject.elementStartLeft  = parseInt(movingObject.elementNode.style.left, 10);
  movingObject.elementStartTop   = parseInt(movingObject.elementNode.style.top,  10);
  movingObject.cursorStartX = x;
  movingObject.cursorStartY = y;

  if (isNaN(movingObject.elementStartLeft)) movingObject.elementStartLeft = 0;
  if (isNaN(movingObject.elementStartTop))  movingObject.elementStartTop  = 0;

  // for IE update z-index.
  //movingObject.elementNode.style.zIndex = ++movingObject.zIndex;

  // attach mouse events
  if (browserObject.isInternetExplorer) {
    document.attachEvent("onmousemove", OnStartMouseMoving);
    document.attachEvent("onmouseup",   OnStopMouseMoving);
    window.event.cancelBubble = true;
    window.event.returnValue = false;
  }
  if (browserObject.isNetscape) {
    document.addEventListener("mousemove", OnStartMouseMoving,   true);
    document.addEventListener("mouseup",   OnStopMouseMoving, true);
    event.preventDefault();
  }
}

function OnStartMouseMoving(event) {

  var x, y;

  // Get cursor position with respect to the page.
  if (browserObject.isInternetExplorer) {
    x = window.event.clientX + document.documentElement.scrollLeft
      + document.body.scrollLeft;
    y = window.event.clientY + document.documentElement.scrollTop
      + document.body.scrollTop;
  }
  if (browserObject.isNetscape) {
    x = event.clientX + window.scrollX;
    y = event.clientY + window.scrollY;
  }

  // moving object to move with respect to it's previous location.
  movingObject.elementNode.style.left = (movingObject.elementStartLeft + x - movingObject.cursorStartX) + "px";
  movingObject.elementNode.style.top  = (movingObject.elementStartTop  + y - movingObject.cursorStartY) + "px";

  if (browserObject.isInternetExplorer) {
    window.event.cancelBubble = true;
    window.event.returnValue = false;
  }
  if (browserObject.isNetscape)
    event.preventDefault();
}

function OnStopMouseMoving(event) {

  // de attach mouse events
  if (browserObject.isInternetExplorer) {
    document.detachEvent("onmousemove", OnStartMouseMoving);
    document.detachEvent("onmouseup",   OnStopMouseMoving);
  }
  if (browserObject.isNetscape) {
    document.removeEventListener("mousemove", OnStartMouseMoving,   true);
    document.removeEventListener("mouseup",   OnStopMouseMoving, true);
  }
}