[рони]

Ramundo,

<INPUT type="text" id = "up"  >
<script>
 function filter_input(e, regexp) {
   //	alert (e);
  	 e= e || window.event;

	 var target=e.target || e.srcElement;

    var code =  e.charCode || e.keyCode;
    if (code<32 ||  e.ctrlKey || e.altKey) return;

    var text=String.fromCharCode(code);
    if (!regexp.test(text))
	{
		if (e.preventDefault) e.preventDefault();
		if (e.returnValue) e.returnValue = false;
		return false;
	};

 return true;
}
document.getElementById("up").addEventListener("keypress", function(event){return filter_input(event, /\d/)}, false);
</script>