function progresso_tecla(obj, limite) {
          var progresso = document.getElementById("progresso");  
		  var limite_char = new Number(limite);
		  var ancho=(limite_char+50);
          if (obj.value.length < limite_char) {
            progresso.style.backgroundColor = "#FFFFFF";    
            progresso.style.backgroundImage = "url(textarea.png)";    
            progresso.style.color = "#000000";
            var pos = ancho-parseInt((ancho*parseInt(obj.value.length))/limite_char);
            progresso.style.backgroundPosition = "-"+pos+"px 0px";
          } else {
			var texto_aux = obj.value;
			texto_aux = texto_aux.substr(0, limite_char);
			obj.value = texto_aux;
            progresso.style.backgroundColor = "#CC0000";    
            progresso.style.backgroundImage = "url()";    
            progresso.style.color = "#FFFFFF";
          } 
          progresso.innerHTML = "("+obj.value.length+" / "+limite_char+")";
        }