Problem with planning view with Internet Explorer 10

function changePlanningColumn(col,status,order) {
	if (status) {
	  //order=planningColumnOrder.indexOf('Hidden'+col);
	  order=dojo.indexOf(planningColumnOrder,'Hidden'+col);
	  planningColumnOrder[order]=col;
	  movePlanningColumn(col,col);
	} else {
	  //order=planningColumnOrder.indexOf(col);
	  order=dojo.indexOf(planningColumnOrder,col);
	  planningColumnOrder[order]='Hidden'+col;
	} 
	dojo.xhrGet({
		url: '../tool/savePlanningColumn.php?action=status&status='
			+ ((status)?'visible':'hidden')+'&item='+col,
		handleAs: "text",
		load: function(data,args) { },
		error: function() { }
	  });	
}