Fixed Column plugin header width not aligne

Firstly, i want to appreciate this amazing work. Every day i discover more impressive features in datatables. Datatables is a life saver. Great work!

I have a small problem when using Fixed columns. The width of the header <th> cells are not aligning with the width of the body of the fixed columns.
Here is my debug code #ewefuw.

This is the code:

               var reportsTable = $('#reportsTable').dataTable({
			"aoColumnDefs": [
				{bSortable:false, "aTargets": ['noSort']},
				{bSearchable: false , "aTargets": ['noSearch']}, 
				{sSearchable: false , "aTargets": ['noSearch']}				
			],
			"bSortClasses":false,
			"bJQueryUI": true,
			"iDisplayLength": 5,
			"bFilter": true,
			"aLengthMenu": [5, 10, 15, 20, 25, 50],
			"sScrollX": "100%",		
			"bScrollCollapse": true, 			
			"bScrollAutoCss": true,
			"bAutoWidth":true,
			"sPaginationType": "full_numbers",
			"sDom": '<"H"<"toolbar"><C>><fr>t<"F"lip>',
			"oColVis": {
				"buttonText": btnTxt, 				
				"aiExclude": aiExcludeArr				
			}
				
		});
		
		var oFC = new FixedColumns( reportsTable, {
			"iLeftColumns": 4,
			"sHeightMatch": "auto"			
		});

Please Help...