New Post: Error after UpdateListItems - The file has been modified by SHAREPOINT\system on 18 Feb 2014 12:00:13 -080

Hi, when I put the updatelistitems in $(document).ready() in editform of document library, I always get
the error like

__ _"The file has been modified by SHAREPOINT\system on 18 Feb 2014 12:00:13 -0800" ___

it prevents clicking "Save" button to continue - but there is no errors - the field get updated.
so could anybody help to disable this error message and let the save button go?
many thanks!

the below is the code:

$().SPServices({
     operation: "UpdateListItems",
     async: false,
     batchCmd: "Update",
    listName: "MyList",
    ID: MyItemID,
    valuepairs: [[FieldName, FieldValues]],  
    completefunc: function (xData, Status){
    if(Status != 'success'){
                         //show error message here
                         //alert(xData.responseText);
     }        
    }
 });