You can click everywhere in the Header to sort a column, not just in the narrow region near the edge of the header.
Check this out : http://dojotoolkit.org/reference-guide/1.8/dojox/grid/EnhancedGrid.html#dojox-grid-enhancedgrid
Update1:
Maybe it's a bug - i found a report here: https://bugs.dojotoolkit.org/ticket/17086 So I would give it a try and load the scripts from an extern Source like in the fiddler example.
Please can you explain why you load your dojoConfig with the number "1" exept the Parameter true? Never seen this befor. I thought this where Boolen only. Try to set the config to the header like:
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Demo: Layout with Dijit</title>
<script type="text/javascript">
var dojoConfig = {
parseOnLoad: true,
isDebug: true,
locale: 'en-us',
extraLocale: ['ja-jp']
};
</script>
and the load your dojo files.
<script type="text/javascript" src="//ajax.googleapis.com/ajax/libs/dojo/1.8/dojo/dojo.js"></script>
</head>
Also i would add data-dojo-type="dojox.grid.EnhancedGrid" to your Div-Area
<div id="file-table" data-dojo-type="dojox.grid.EnhancedGrid" style="width: 100%; height: 700px;"></div>
Regards