function menuDesplegable(){
    var elems=$('menu').getElementsByTagName('li');    
    desplegando=false;     
    for(var k=0;k<elems.length;k++){ 
        if(elems[k].parentNode.id=='menu' && elems[k].getElementsByTagName('ul').length>0){     
            elems[k].efecto = new fx.Height( elems[k].getElementsByTagName('ul')[0]   , {duration: 250, transition : fx.circ, onComplete: function()
  {
    desplegando=false;
  }
             });
            //elems[k].altura= (elems[k].getElementsByTagName('ul')[0].className=='corto') ? 75 : 133;
            
            
            
            elems[k].onmouseover=function(e){         
                  if (!e) var e = window.event;
                    for(var q=0;q<elems.length;q++){ 
                         if(elems[q].parentNode.id=='menu' && elems[q].getElementsByTagName('ul').length>0 && elems[q].getElementsByTagName('ul')[0].offsetHeight>70)    elems[q].onmouseout(e);
                    }                  
                  
                  if(!desplegando &&  this.getElementsByTagName('ul')[0].offsetHeight<50){
                    desplegando=true;        
                      this.efecto.toggle();            
                    //this.efecto.custom(0,this.altura);
                  }
            }
            elems[k].onmouseout=function(e){ 
                 if (!e) var e = window.event;
	      var relTarg = e.relatedTarget || e.toElement;  
	      if(this!=relTarg && !esAncestro(this,relTarg)){
	         // this.efecto.hide();
	         if(this.getElementsByTagName('ul')[0].offsetHeight>10){
	           this.efecto.toggle();   
	         }
	        // this.efecto.custom(this.altura,0);
	      }
                 
            }
	
            elems[k].onmouseover;
        }  
    }
}