Problem fnSettings().aoColumns has a null value when using FixedColumn

Hi all,

I've got a problem on one of my pages with FixedColumn using IE8 (i've no choice about that, sorry :) ).
I've got 5 pages with the exact same code to use DataTable and FixedColumn. 4 of them are working well but for the last one i've got this error message (IE8 dev tools) :

Line: 29
Error : 'fnSettings().aoColumns' has a Null value or is not an object.

Here is my code :

var oTable = $('#ctl00_ContentPlaceHolder2_tab_pdp').dataTable({
	// height scroll
	"sScrollY": tabMaxHeightPDP() + "px",
	// width scroll
	"sScrollX": "4060px",
	"sScrollXInner": "4060px",
	"bScrollCollapse": true,

	// pagination
	"bPaginate": true,

	// show/hide columns
	"sDom": 'C<"clear">lfrtip',
	"oColVis": {
		"aiExclude": [0, 1, 2] // colonnes à ne pas masquer
	},
	
	// init sorting
	"aaSorting": [[1, "asc"]]
});
new FixedColumns(oTable, {
	// three fixed columns
	"iLeftColumns": 3, 
	"iLeftWidth": 560
});

Thanks ;)