order by problem with stored procedure

Hi,
I try to short dinamically the result my stored procedure. SP seems not validate the field passed.

I try durectly from my query sw with -ORDER BY 'no word' - and effecly ther is no error and record return are the same present ordered into the table.
So I think the problem is in the SP.
The field passed is read like varchar.
No i'ts impossible pass teh real name dinamically or I must use numbers?
Like ORDER BY 1....

Thanks,
Alen Italy

	PROCEDURE Utenti(
		strCookieMD5 IN varchar2,
		intDaRs IN number,
		intArs IN number,
		strOrdinamento IN varchar2,
		OBJ_CUR_Utenti OUT CUR_Utenti
		)
	AS
	var_TotaleRs number;
	BEGIN



		--Tot record

		SELECT
			NVL(Count(*),0)
		INTO
		 	var_TotaleRs
		FROM UTENTI
		WHERE (STATO = 1);



		--Rs principale

		OPEN OBJ_CUR_Utenti FOR

			SELECT
				u.*,
				var_TotaleRs TotRs,
				rownum SeqNum,
				strOrdinamento Ord
			FROM UTENTI u
			WHERE (STATO = 1)
			ORDER BY strOrdinamento;

	END Utenti;