I have a function that loads some text and puts it into a div. Here it is:

Code:
function MessageGet()
{
MessageXMLDoc("ajaxget?messages",function()
  {
  if (xmlhttp3.readyState==4 && xmlhttp.status==200)
    {
    document.getElementById("message").innerHTML=xmlhttp3.responseText;
    }
  if (xmlhttp3.readyState==4 && xmlhttp.status!=200)
    {
    document.getElementById("message").innerHTML="";
    }
  if (xmlhttp3.readyState==4)
    {
    setTimeout('MessageGet()',1000);
    }
  });
}
At first it works fine, but at seemingly random points, it just... stops. What am I doing wrong? Any help at all would be appreciated.

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