divScroll=function(
	objId
){
	/*this.error=document.createElement('DIV');
	this.error.style.position="absolute";
	this.error.style.top='200px';
	this.error.style.left='150px';
	this.error.style.border='1px solid white';
	document.body.appendChild(this.error);*/
	var self=this;
	//creo el timeout para subir y bajar
	this.timeoutUp=new Object;
	this.timeoutDown=new Object;
	//variable que indica si se está arrastrando o no
	this.dragging=false;
	//variable que idica si estamos encima del contenido
	this.onContent=false;
	//clonamos el div con el contenido
	//para calcular el ancho y alto real, debemos darle a la capa origen el overflow hidden para que se acople
	document.getElementById(objId).style.overflow='hidden';
	var ancho=document.getElementById(objId).offsetWidth;
	var alto=document.getElementById(objId).offsetHeight;
	this.dvContent=document.getElementById(objId).cloneNode(true);
	//estilos de la mascara
	this.dvMask=document.createElement('DIV');
	this.dvMask.style.position='relative';
	this.dvMask.style.zIndex='1';
	this.dvMask.style.height=alto+'px';	
	this.dvMask.style.width=ancho+'px';
	this.dvMask.style.overflow='hidden';
	//this.dvMask.id='submain';
	this.dvMask.className='scrollMask';
	//añadimos la máscara al documento, y eliminamos el div con el contenido, ya que lo tenemos clonado en this.dvContent
	document.getElementById(objId).parentNode.insertBefore(this.dvMask, document.getElementById(objId))
	document.getElementById(objId).parentNode.removeChild(document.getElementById(objId));
	//estilos del contenido
	this.dvContent.className='scrollContent';
	this.dvContent.id="";
	this.dvContent.style.position='absolute';
	this.dvContent.style.top='0px';
	this.dvContent.style.left='0';
	//al ponerse encima del conenido activo una variable, que servira para hacer scroll al girar la rueda
	this.dvContent.onmouseover=function(){
		self.onContent=true;
	}
	this.dvContent.onmouseout=function(){
		self.onContent=false;
	}
	this.dvMask.appendChild(this.dvContent);
	//estilos de la barra
	this.dvScroll=document.createElement('DIV');
	this.dvScroll.style.position='absolute';
	this.dvScroll.style.height=alto+'px';
	this.dvScroll.style.right='0';
	this.dvScroll.style.top='0';
	this.dvScroll.className='scrollBar';
	this.dvScroll.onmousedown=function(){
		//ponemos esto para que no se ralle al pinchar en el drag
		return false;
	}
	this.dvScroll.onclick=function(e){
		//al hacer click sobre la barra hacemos que se desplace la mitad de la distancia entre el click y la posicion del scroll hacia arriba o abajo
		if (document.all){
			var obj=event.srcElement;
			layerY=event.offsetY;
		}
		else{
			var obj=e.target;
			layerY=e.layerY
		}
		if (obj==this){
			if (self.dvDragPosY>layerY){
				if (self.dvDragPosY>layerY){
					self.dvDragPosY=self.dvDragPosY-parseInt(((self.dvDragPosY-layerY)/2));
				}
				if (self.dvDragPosY<self.dvUp.offsetHeight){
					self.dvDragPosY=self.dvUp.offsetHeight;
				}
			}else{
				if (self.dvDragPosY+self.dvDrag.offsetHeight<layerY){
					self.dvDragPosY=self.dvDragPosY+parseInt(((layerY-self.dvDragPosY-self.dvDrag.offsetHeight)/2));
				}
				if (self.dvDragPosY+self.dvDrag.offsetHeight>self.dvScroll.offsetHeight-self.dvDown.offsetHeight){
					self.dvDragPosY=self.dvScroll.offsetHeight-self.dvDown.offsetHeight-self.dvDrag.offsetHeight;
				}
			}
			self.mueveContenido();
		}
	}
	//flecha_arriba
	this.dvUp=document.createElement('DIV');
	this.dvUp.style.position='absolute';
	this.dvUp.style.top='0';
	this.dvUp.style.right='0';
	this.dvUp.className='scrollBar_Up';
	this.dvUp.onmousedown=function(){
		self.timeoutUp=setTimeout(self.goUp, 5);
	};
	this.dvUp.onmouseup=function(){
		self.timeoutUp=clearTimeout(self.timeoutUp);
	};
	this.dvUp.onmouseout=function(){
		self.timeoutUp=clearTimeout(self.timeoutUp);
	}
	this.dvScroll.appendChild(this.dvUp);
	//flecha_abajo
	this.dvDown=document.createElement('DIV');
	this.dvDown.style.position='absolute';
	this.dvDown.style.bottom='0';
	this.dvDown.style.right='0';
	this.dvDown.className='scrollBar_Down';
	this.dvDown.onmousedown=function(){
		self.timeoutDown=setTimeout(self.goDown, 5);
	};
	this.dvDown.onmouseup=function(){
		self.timeoutDown=clearTimeout(self.timeoutDown);
	};
	this.dvDown.onmouseout=function(){
		self.timeoutDown=clearTimeout(self.timeoutDown);
	}
	this.dvScroll.appendChild(this.dvDown);
	//barra de arrastre
	this.dvDrag=document.createElement('DIV');
	this.dvDrag.className='scrollBar_Drag';
	this.dvDrag.style.position='absolute';
	this.dvDrag.right='0';
	this.dvDrag.onmousedown=function(e){
		//deshabilito la seleccion de texto
		document.onselectstart=self.disableselect;
		if (window.sidebar){
			document.onmousedown=self.disableselect
			document.onclick=self.reEnable
		}
		self.dragging=true;
		self.dvDrag.className='scrollBar_DragClick';
		if (document.all)
			self.clickY=event.offsetY;
		else
			self.clickY=e.layerY;
	}
	this.dvDrag.onmouseup=function(e){
		//habilito la seleccion de texto
		document.onselectstart=self.reEnable;
		if (window.sidebar){
			document.onmousedown=self.reEnable
			document.onclick=self.reEnable
		}
		self.dragging=false;
		self.dvDrag.className='scrollBar_Drag';
	}
	//calculo la posicion del elemento drag
	this.dvScroll.appendChild(this.dvDrag);
	var element=this.dvDrag;
    this.dvDragY = 0;
	this.clickY=0;
    do {
      this.dvDragY += element.offsetTop;
    } while (element=element.offsetParent)
	this.dvDragY=document.getElementById('content').offsetTop;
    this.dvDragY+=24;
	//this.dvDragPosY=this.dvDragY;
	this.dvDragPosY=0;
	
	//añado los eventos de arrastrar
	document.onmousemove=function(e){
		if (self.dragging){
			var posy=0;
			if (document.all){
				posy=event.clientY+document.documentElement.scrollTop;
			}else{
				posy=e.pageY;
			}
			
			posy=posy-self.dvDragY-self.clickY;
			if (posy<self.dvUp.offsetHeight)
				posy=self.dvUp.offsetHeight;
			else{
				if (posy>self.dvScroll.offsetHeight-self.dvDown.offsetHeight-self.dvDrag.offsetHeight)
					posy=self.dvScroll.offsetHeight-self.dvDown.offsetHeight-self.dvDrag.offsetHeight;
				else
					posy=posy;
			}
			//muevo el drag
			self.dvDrag.style.top=String(posy)+'px';
			self.dvDragPosY=posy;
			//muevo el contenido
			if (posy==self.dvUp.offsetHeight){
				posy=0;
			}else{
				posy=(self.relacion*posy)*-1;
				if (posy>0)
					posy=0;
				else{
					if (posy<(self.dvContent.offsetHeight-self.dvMask.offsetHeight)*-1)
						posy=parseInt(self.dvContent.offsetHeight-self.dvMask.offsetHeight)*-1;
				}
			}
			self.dvContent.style.top=String(posy)+'px';
		}else{

		}
	}
		
	this.mueveContenido=function(){
		var posy=0;
		self.dvDrag.style.top=String(self.dvDragPosY)+'px';
		if (self.dvDragPosY==self.dvUp.offsetHeight){
			posy=0;
		}else{
			posy=parseInt(self.relacion*self.dvDragPosY)*-1;
			if (posy>0)
				posy=0;
			else{
				if (posy<(self.dvContent.offsetHeight-self.dvMask.offsetHeight)*-1)
					posy=(self.dvContent.offsetHeight-self.dvMask.offsetHeight)*-1;
			}
		}
		self.dvContent.style.top=String(posy)+'px';
	}
	document.onmouseup=function(e){
		//habilito la seleccion de texto
		document.onselectstart=self.reEnable;
		if (window.sidebar){
			document.onmousedown=self.reEnable
			document.onclick=self.reEnable
		}
		self.dragging=false;
		self.dvDrag.className='scrollBar_Drag';
	}
	//añado el evento de la rueda para firefox
	if (this.dvContent.addEventListener)
		this.dvContent.addEventListener('DOMMouseScroll', function(event){
			var delta;
			if (event.wheelDelta) { /* IE/Opera. */
				delta = event.wheelDelta/120;
				/**In Opera 9, delta differs in sign as compared to IE. */
		        if (window.opera)
		            delta = -delta;
		    } else if (event.detail) { /** Mozilla case. */
		        /** In Mozilla, sign of delta is different than in IE. * Also, delta is multiple of 3.*/
		        delta = -event.detail/3;
		    }
			delta=delta*15*-1;
			self.dvDragPosY=self.dvDragPosY+delta;
			if (self.dvDragPosY<self.dvUp.offsetHeight){
				self.dvDragPosY=self.dvUp.offsetHeight;
			}
			if (self.dvDragPosY+self.dvDrag.offsetHeight>self.dvScroll.offsetHeight-self.dvDown.offsetHeight){
				self.dvDragPosY=self.dvScroll.offsetHeight-self.dvDown.offsetHeight-self.dvDrag.offsetHeight;
			}
			self.mueveContenido();
			event.returnValue = false;
		}, false);
	//añado el evento de la rueda para explorer
	this.dvContent.onmousewheel = function(){
		//event=window.event;
		var delta;
		if (event.wheelDelta) { /* IE/Opera. */
			delta = event.wheelDelta/120;
			/** In Opera 9, delta differs in sign as compared to IE. */
			if (window.opera)
				delta = -delta;
		} else if (event.detail) { /** Mozilla case. */
			/** In Mozilla, sign of delta is different than in IE. * Also, delta is multiple of 3.*/
			delta = -event.detail/3;
		}
		delta=delta*15*-1;
		self.dvDragPosY=self.dvDragPosY+delta;
		if (self.dvDragPosY<self.dvUp.offsetHeight){
			self.dvDragPosY=self.dvUp.offsetHeight;
		}
		if (self.dvDragPosY+self.dvDrag.offsetHeight>self.dvScroll.offsetHeight-self.dvDown.offsetHeight){
			self.dvDragPosY=self.dvScroll.offsetHeight-self.dvDown.offsetHeight-self.dvDrag.offsetHeight;
		}
		self.mueveContenido();
		event.returnValue = false;
	}
	
	this.dvMask.appendChild(this.dvScroll);
	
	this.dvContent.style.width=ancho-this.dvScroll.offsetWidth+'px';
	
	//si el drag no tiene alto, lo calculo
	if (this.dvDrag.offsetHeight==0){
		aux=this.dvContent.offsetHeight-this.dvMask.offsetHeight;
		if (aux<0){
			this.dvScroll.style.display='none';
		}else{
			if (aux<this.dvScroll.offsetHeight){
				this.dvDrag.style.height=(this.dvScroll.offsetHeight-aux)+'px';
			}else{
				this.dvDrag.style.height=parseInt(this.dvScroll.offsetHeight/(aux/this.dvScroll.offsetHeight))+'px';
			}
		}
	}
	
	//calculo la relación movimiento del drag-movimiento del texto
	this.relacion=(this.dvContent.offsetHeight-this.dvMask.offsetHeight)/(this.dvScroll.offsetHeight-this.dvUp.offsetHeight-this.dvDown.offsetHeight-this.dvDrag.offsetHeight);
	this.relacionIns=(this.dvScroll.offsetHeight-this.dvUp.offsetHeight-this.dvDown.offsetHeight-this.dvDrag.offsetHeight)/(this.dvContent.offsetHeight-this.dvMask.offsetHeight);
	//pongo la barra de arastre en su posicion inicial
	this.dvDrag.style.top=String(this.dvUp.offsetHeight)+'px';
	
	this.goUp=function(){
		var pos=parseInt(self.dvContent.style.top.substr(0, self.dvContent.style.top.length-2));
		if (pos+5<0){
			pos=pos+5;
			self.dvContent.style.top=String(pos)+'px';
			self.timeoutUp=setTimeout(self.goUp, 5);
			self.dvDragPosY=parseInt(pos*self.relacionIns)*-1+self.dvUp.offsetHeight;
			self.dvDrag.style.top=self.dvDragPosY+'px';
		}else{
			self.dvContent.style.top='0px';
			self.dvDragPosY=self.dvUp.offsetHeight;
			self.dvDrag.style.top=self.dvDragPosY+'px';
		}
	}
	
	this.goDown=function(){
		var pos=parseInt(self.dvContent.style.top.substr(0, self.dvContent.style.top.length-2));
		var innerAlto=parseInt(alto)-self.dvContent.offsetHeight;
		if (pos-5>innerAlto){
			pos=pos-5;
			self.dvContent.style.top=String(pos)+'px';
			self.timeoutDown=setTimeout(self.goDown, 5);
			self.dvDragPosY=parseInt(pos*self.relacionIns)*-1+self.dvUp.offsetHeight;
			self.dvDrag.style.top=self.dvDragPosY+'px';
		}else{
			self.dvContent.style.top=String(innerAlto)+'px';
			self.dvDragPosY=self.dvScroll.offsetHeight-self.dvDown.offsetHeight-self.dvDrag.offsetHeight;
			self.dvDrag.style.top=self.dvDragPosY+'px';
		}
		
	}
	//funciones que habilitan o deshabilitan la seleccion de texto, ya que al arrastar el scroll se selecciona el texto
	this.disableselect=function(e){
		return false
	}
	this.reEnable=function(){
		return true
	}
}