var movedownvar;
var moveupvar;
var speed=20;
var iens6 = document.all||document.getElementById;
var ns4 = document.layers;


function movedown(){

 if(  iens6 && parseInt( crossobj.style.top ) >= ( contentheight * (-1)+374)  )
 {
   crossobj.style.top = parseInt(crossobj.style.top) - speed + "px";
 } 
 else if( ns4 && crossobj.top >= (contentheight * (-1) + 374)  )
 {
   crossobj.top -= speed;
   movedownvar = setTimeout( "movedown()", 20 );
 }


}


function moveup(){

  if(  (iens6 && parseInt( crossobj.style.top ) <= 0)  )
  {
    crossobj.style.top=parseInt(crossobj.style.top)+speed+"px";
  }
  else if(  (ns4 && crossobj.top <= 0)  )
  {
    crossobj.top += speed;
  }

  

  moveupvar=setTimeout("moveup()",20);
}

function getcontent_height(){
  
  if(iens6)
  {
    contentheight=crossobj.offsetHeight;
  }  
  else if(ns4)
  {
    document.nscontainer.document.nscontent.visibility="show";
  }

}


function scrollinit(){

  if (window.addEventListener)
    window.addEventListener('DOMMouseScroll', wheel, false);

  document.onmousewheel = wheel;
}



function scrollstop(){

  if (window.removeEventListener)
    window.removeEventListener('DOMMouseScroll', wheel, false);

  document.onmousewheel = scroll;
  window.onmousewheel = scroll;
}



function handle(delta) {	

  if (delta < 0)
    movedown(); 

  clearTimeout(movedownvar);

  if (delta > 0)
    moveup();
  
  clearTimeout(moveupvar);
}


function wheel(event){
  var delta = 0;

  if (!event) event = window.event;

  if (event.wheelDelta) 
  {
    delta = event.wheelDelta/120; 

  }else if (event.detail) 
  {
    delta = -event.detail/3;
  }

  if (delta)
    handle(delta);

  if (event.preventDefault)
    event.preventDefault();

  event.returnValue = false;
}