Ajax function in javascript can not check whether the XML is empty?

[patsalko]

\[code\] error: function(x, t, m) { if(t === "timeout") { document.location.reload(true); } else if(t === "parsererror") { alert("Error in reading the XML file."); } else if(t === "abort") { alert("The XML request is aborted."); } else{ alert("Encounter error in reading XML."); } }\[/code\]These are the default error-checking method provided by ajax function, however, it does not check whether the file is empty or not. Is there any way to fix this problem? Also , are there other typical error cases I should handle? Thanks