Bug when filtering by column with spaces on name

[InsomniumBR]

Hello,

I have just found a small bug when using column name with spaces.
Since I am not an expert on PHP, I would suggest any of you a little help on fixing this.

The column name specified was "Dias na atividade".

Thanks in advance,

Error message:
"An error occured rendering the grid: SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'na atividade ASC LIMIT 20' at line 15, query was: SELECT t.* FROM (SELECT DATE_FORMAT(sales_flat_order.created_at, '%d/%m/%Y') AS 'Data', sales_flat_order.increment_id AS 'Pedido', sales_flat_order.entity_id AS order_id, CONCAT(TRIM(sales_flat_order.customer_firstname), ' ', TRIM(sales_flat_order.customer_lastname)) AS 'Cliente', sales_order_status.label AS 'Status', datediff(now(), sales_flat_order.created_at) AS 'Dias na atividade' FROM sales_flat_order_status_history history INNER JOIN (select parent_id, max(entity_id) lastId from sales_flat_order_status_history group by parent_id) tLastDate ON (history.entity_id = tLastDate.lastId) INNER JOIN sales_flat_order ON sales_flat_order.entity_id = history.parent_id INNER JOIN sales_order_status ON history.status = sales_order_status.status WHERE history.status IN ('processing' , 'preimpressao', 'producao','refacao','expedicao') ORDER BY datediff(now(), sales_flat_order.created_at) DESC) AS t ORDER BY Dias na atividade ASC LIMIT 20"