function initMoving(target, position, topLimit, btmLimit) 
{ 
  if (!target) 
    return false; 

  var obj = target; 
  obj.initTop = position; 
  obj.topLimit = topLimit; 
  obj.bottomLimit = document.documentElement.scrollHeight - btmLimit; 

  obj.style.position = "absolute"; 
  obj.top = obj.initTop; 
  obj.left = obj.initLeft; 

  if (typeof(window.pageYOffset) == "number") 
  { 
    obj.getTop = function() 
    { 
      return window.pageYOffset; 
    } 
  } 
  else if (typeof(document.documentElement.scrollTop) == "number") 
  { 
    obj.getTop = function() 
    { 
      return document.documentElement.scrollTop; 
    } 
  } 
  else 
  { 
    obj.getTop = function() 
    { 
      return 0; 
    } 
  } 

  if (self.innerHeight) 
  { 
    obj.getHeight = function() 
    { 
      return self.innerHeight; 
    } 
  } 
  else if(document.documentElement.clientHeight) 
  { 
    obj.getHeight = function() 
    { 
      return document.documentElement.clientHeight; 
    } 
  } 
  else 
  { 
    obj.getHeight = function() 
    { 
      return 500; 
    } 
  } 

  obj.move = setInterval(function() 
  { 
    if (obj.initTop > 0) 
    { 
      pos = obj.getTop() + obj.initTop; 
    } 
    else 
    { 
      pos = obj.getTop() + obj.getHeight() + obj.initTop; 
      //pos = obj.getTop() + obj.getHeight() / 2 - 15; 
    } 

    if (pos > obj.bottomLimit) 
      pos = obj.bottomLimit; 
    if (pos < obj.topLimit) 
      pos = obj.topLimit; 

    interval = obj.top - pos; 
    obj.top = obj.top - interval / 3; 
    obj.style.top = obj.top + "px"; 
  }, 30) 
}