var http_request = false;
    function makeRequest(url) {
        http_request = false;

        if (window.XMLHttpRequest) { // Mozilla, Safari,...
            http_request = new XMLHttpRequest();
            if (http_request.overrideMimeType) {
                http_request.overrideMimeType('text/xml');
                // See note below about this line
            }
        } else if (window.ActiveXObject) { // IE
            try {
                http_request = new ActiveXObject("Msxml2.XMLHTTP");
            } catch (e) {
                try {
                    http_request = new ActiveXObject("Microsoft.XMLHTTP");
                } catch (e) {}
            }
        }

        if (!http_request) {
            alert('Giving up :( Cannot create an XMLHTTP instance');
            return false;
        }
        http_request.onreadystatechange = alertContents;
        http_request.open('GET', url, false);
        http_request.send(null);
		
		return http_request.responseText;
    }

    function alertContents() {

        if (http_request.readyState == 4) {
            if (http_request.status == 200) {
                //return http_request.responseText;
            } else {
                alert('There was a problem with the request.');
            }
        }
 
    }
    
    
	//
	// Função recebe uma string convert para encode64 e
	// devolve o resultado
	//
	function encode64(input) {
	 var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
	   var output = "";
	   var chr1, chr2, chr3;
	   var enc1, enc2, enc3, enc4;
	   var i = 0;
	 
	   do {
	      chr1 = input.charCodeAt(i++);
	      chr2 = input.charCodeAt(i++);
	      chr3 = input.charCodeAt(i++);
	 
	      enc1 = chr1 >> 2;
	      enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
	      enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
	      enc4 = chr3 & 63;
	 
	      if (isNaN(chr2)) {
	         enc3 = enc4 = 64;
	      } else if (isNaN(chr3)) {
	         enc4 = 64;
	      }
	 
	      output = output + keyStr.charAt(enc1) + keyStr.charAt(enc2) +
	         keyStr.charAt(enc3) + keyStr.charAt(enc4);
	   } while (i < input.length);
	  
	   return output;
	
	}