function Ajax() {
  this.req = null;
  this.url = null;
  this.method = 'GET';
  this.async = true;
  this.status = null;
  this.statusText = '';
  this.postData = null;
  this.readyState = null;
  this.responseText = null;
  this.responseXML = null;
  this.handleResp = null;
  this.responseFormat = 'text', // 'text', 'xml', or 'object'
  this.mimeType = null;
  
  //////////////////
  // CONSTRUCTOR //
  this.init = function() {
    if (!this.req) {
      try {
      // Try to create object for Firefox, Safari, IE7, etc.
      this.req = new XMLHttpRequest();
      }
      catch (e) {
        try {
        // Try to create object for later versions of IE.
        this.req = new ActiveXObject('MSXML2.XMLHTTP');
        }
        catch (e) {
          try {
          // Try to create object for early versions of IE.
          this.req = new ActiveXObject('Microsoft.XMLHTTP');
          }
          catch (e) {
          // Could not create an XMLHttpRequest object.
          return false;
          }
        }
      }
    }
    return this.req;
  };
  
  
  ////////////////////
  // ERROR HANDLING //
  this.handleErr = function() {
    var errorWin;
    try {
      errorWin = window.open('', 'errorWin');
      errorWin.document.body.innerHTML = this.responseText;
    }
    catch (e) {
      alert('An error occurred, but the error message cannot be '
      + 'displayed. This is probably because of your browser\'s '
      + 'pop-up blocker.\n'
      + 'Please allow pop-ups from this web site if you want to '
      + 'see the full error messages.\n'
      + '\n'
      + 'Status Code: ' + this.req.status + '\n'
      + 'Status Description: ' + this.req.statusText);
    }
  };
      
  ///////////////////////////
  // WHEN STOP IS PRESSED //
  this.abort = function() {
    if (this.req) {
      this.req.onreadystatechange = function() { };
      this.req.abort();
      this.req = null;
    }
  };
  
  /////////////////////
  // REQUEST METHOD //
  this.doReq = function() {
    if (!this.init()) {
      alert('Could not create XMLHttpRequest object.');
      return;
    }
    
    // don't use cache you god damn IE
    var rnd = new Date();
    rnd = rnd.getTime();
    if ( this.url.indexOf('?') > -1 ) {
      this.url += "&rnd="+rnd;
    } else {
      this.url += "?rnd=rnd";
    } 
    
    this.req.open(this.method, this.url, this.async); //  method: GET|POST (uppercase!)
    
    if (this.method == "POST") {
      this.req.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
    } 
    
    var self = this; // Fix loss-of-scope in inner function
    this.req.onreadystatechange = function() {
      var resp = null;
      if (self.req.readyState == 4) { // 4=completed
        switch (self.responseFormat) {
          case 'text':
            resp = self.req.responseText;
            break;
          case 'xml':
            resp = self.req.responseXML;
            break;
          case 'object':
            resp = req;
            break;
        }
        if (self.req.status >= 200 && self.req.status <= 299) {
          self.handleResp(resp);
        }
        else {
          //self.handleErr(resp);
        }
      }
    };
    this.req.send(this.postData);
  };


  //////////////////////////////////////
  // PERFORM XHTTP-REQUEST USING GET //  
  this.doGet = function(url, hand, format) {
    this.url = url;
    this.handleResp = hand;
    this.responseFormat = format || 'text';
    this.method = 'GET';
    this.doReq();
  };
  
  
  ///////////////////////////////////////
  // PERFORM XHTTP-REQUEST USING POST //    
  this.doPost = function(url, postData, hand, format) {
    this.url = url;
    this.handleResp = hand;
    this.responseFormat = format || 'text';
    this.method = 'POST';
    this.postData = postData;
    this.doReq();
  };
  
  
}