Here's correct way to process SQL cursor. The FETCH w/o INTO clause creaes record set wityn one record.

  FETCH NEXT FROM curCerti
   Into  @CertNum,
      @Inversionista,
      @Nombre,
      @Tipo,
      @Descripcion,
      @ValorInicial,
      @InteresAnual

 WHILE @@FETCH_STATUS = 0
  BEGIN

	SET 
	....
	INSERT
	
	  FETCH NEXT FROM curCerti
   Into  @CertNum,
      @Inversionista,
      @Nombre,
      @Tipo,
      @Descripcion,
      @ValorInicial,
      @InteresAnual
  END

Don't reinvent the weel, read BOL. :)

>Sergey it didn't work it keeps returning the last record fetched. If I run the SP with the SQL Query Analizer I get 2 result sets but I'm only interested on the second one, the @Datos cursor that is.
>
>Enmanuel
>
>>

--Return Select * From Datos
>>Select * From @Datos

>>