function stateChanged5()
{

    if (request5.readyState==4)
    {
    	document.getElementById(displayElem).innerHTML=request5.responseText;
    }
    else
    {
    	document.getElementById(displayElem).innerHTML="";
    }
}

var counter = 0;

function makeRequest() {
  var xhr = // yada yada yada, get your XmlHttpRequest instance
  xhr.onreadystatechange = function() {
    if(this.readyState == 4) {
      // Do whatever, based on the counter variable
      counter += 1
      if(counter < 5)
        makeRequest();
    }
    else {
      // Do whatever, based on the counter variable
    }
  }
  xhr.open();
}