Uploaded lost files

Question: Upload multiple files (for example, 5), the first to transfer all the files finish.
The second re-transmission of five files, only 2 file successfully, there are 3 files missing.

uploadify version: 2.0, 2.1.4
Browser version: Firefox 4.0
Jquery: 1.4.4
Is this what the problem is


$("#uploadify").uploadify({
'uploader' : 'swf/uploadify.swf',
'script' : 'project_docs_upload.php',
'cancelImg' : 'img/uploadify-cancel.png',
'queueID' : 'fileQueue',
'auto' : false,
'multi' : true,
'removeCompleted' : true,
'buttonText' : 'Select Files',
'sizeLimit' : 1073741824,
'onSelect' : function (){
$('#start-upload-link').show();
$('#cancel-upload-link').show();
},
'onCancel' : function (){
$('#start-upload-link').hide();
$('#cancel-upload-link').hide();
},
'onAllComplete' : function(event,data){
//alert(data.errors+','+data.allBytesLoaded +','+data.speed );
},
'onComplete' : function (event, queueID, fileObj, response, data) {

var h=eval('(' + response + ')');

'onError' : function (event, queueID, fileObj,errorObj) {
//a=$('#project_docs_list').html();
//$('#project_docs_list').html(a + fileObj.name+','+errorObj.type + ',' +errorObj.info+ '<br/>');
}
});