function quickAjax( url, func, send, extra ) {
	var method = send == null ? 'GET' : 'POST';
	var text = null;
	var req;
	if( window.XMLHttpRequest ) {
		req = new XMLHttpRequest();
		req.onload = function() {
			if( func ) func( req.responseText, extra );
			text = req.responseText;
		}
	} else {
		req = new ActiveXObject( 'Microsoft.XMLHTTP' );
		req.onreadystatechange = function() {
			if( func ) func( req.responseText, extra );
			text = req.responseText;
		}
	}
	try {
		req.open( method, encodeURI( url ), func ? true : false );
	} catch( e ) {
		return 'error en req.open';
	}
	if( method == 'POST' ) {
		req.setRequestHeader( 'Content-type', 'application/x-www-form-urlencoded' );
		req.setRequestHeader( 'Connection', 'close' );
	}
	req.send( send );
	if( ! func ) return text;
}