if (navigator.appVersion.search("MSIE") == -1)
	var IE = false;
else
	var IE = true;

function justNumber(e) {
    tecla = IE? e.keyCode : e.which;
	
    if ((tecla == 0) || (tecla == 8)) {
        return true;
    }
    if ((tecla < 48)||(tecla > 57)) {
        if (IE){
            e.keyCode = 0;
            return false;
        }else{	//caso o browser seja firefox
            e.preventDefault();
            return false;
        }
    }
}

function openAjax() {
	var ajax;
	try {
		ajax = new XMLHttpRequest();
	} catch(ee) {
		try {
			ajax = new ActiveXObject("Msxml2.XMLHTTP");
		} catch(e) {
			try {
				ajax = new ActiveXObject("Microsoft.XMLHTTP");
			} catch(E) {
				ajax = false;
			}
		}
	}
	
	return ajax;
}

function carregarCorpo(pagina){
	var ajax=openAjax();
	ajax.open('GET',pagina, true);

	ajax.onreadystatechange = function(){
											if (ajax.readyState < 4) {
												document.getElementById('corpo').innerHTML="<p style='text-align:center'>Carregando...</p>";
											}
											if (ajax.readyState == 4) {
												if (ajax.status == 200) {
													var varRetorno = ajax.responseText;
														document.getElementById('corpo').innerHTML=varRetorno;
												}
											}
										} 
 	ajax.send(null);			
}