Stored procedure in Firebird

Good Afternoon,
I'm starting in the world of Qt and a Firebird database.And finish the driver installation process and perform operations onthe database insert, update and consultation.
When I started to make stored procedures and run them from Qt did not work. Does not fail and always us that everything was made ​​perfect, but the database does not run.
I am programming in Linux using Qt 2.0.1 and Firebird 2.1
I create a simple stored procedure test which makes it an insert into a table. It works by running the console but when trying to run fromQt does not work and gives me no errors.The SQL code is:

Code:

---

SET TERM ^ ;
CREATE PROCEDURE AGREEGAR_UNO AS 
BEGIN 
insert into JUEGO(CODIGO,ESCRUTINIO,ESTADO,FECHA,HORAINICIO) values (next value for GNECODIGOJUEGO,'111,123,154,169,178','Hi', current_date, current_time);
END^
SET TERM ; ^
GRANT EXECUTE ON PROCEDURE AGREEGAR_UNO TO SYSDBA;

---

The following code will use to connect to firebird from Qt

Code:

---

bool VentanaPrueba::conectar()
{
this->db= QSqlDatabase::addDatabase("QIBASE","Data");
this->db.setDatabaseName("./BD/Data.fdb");
this->db.setPassword("password");
this->db.setUserName("SYSDBA");
if(!db.open())
{
return false;
}
else
return true;
}

---

And this is the code that is responsible for calling the procedure

Code:

---

void VentanaPrueba::procedimiento()
{
if (!this->db.isOpen()) this->conectar();
if(this->db.isOpen())
{ QSqlQuery procedimiento = QSqlQuery::QSqlQuery(this->db);
bool bandera = procedimiento.prepare("EXECUTE PROCEDURE AGREEGAR_UNO");
QString err = procedimiento.lastError().text();
bool respuesta= procedimiento.exec();
//this->db.commit();
if(!respuesta)
{
this->db.close();
}else
{
procedimiento.finish();
this->db.commit();
this->db.close();
}
 
 
}else{
//error
}
 
 
}

---

Thank you very much for your help.