var jS = 0;
var jD = 5;
var numitem = 0;

function sfuma(){
	var myitem = document.getElementById('item'+numitem);
	if(myitem && myitem != null){
		setOpacity(myitem, 20*jS/100);
		jS = jS+1;
		if(jS<=5){			
			setTimeout('sfuma()',36);			
		}
		else{
			jS = 0;
			numitem++;
			setTimeout('sfuma()',36);
		}
	}
	else{
		numitem=0;
	}
}

function desfuma(){
	var myitem = document.getElementById('item'+numitem);
	if(myitem && myitem != null){
		setOpacity(myitem, 20*jD/100);
		jD = jD-1;
		if(jD>=0){			
			setTimeout('desfuma()',36);
		}
		else{
			jD = 5;
			numitem++;
			setTimeout('desfuma()',36);
		}
	}
	else{
		numitem=0;
	}
}

function setOpacity( el, opaciLevel ) {
    if ( el.style.opacity != undefined ) {
        el.style.opacity = opaciLevel;
    } else if( el.style.MozOpacity != undefined ) {
        el.style.MozOpacity = opaciLevel;
    } else if ( el.style.filter != undefined ) {
        var oplvl = Math.round(opaciLevel*100);
        el.style.filter="alpha(opacity=" + oplvl + ")";
    }
}