Date type parameters do not work package procedure

Question

a cordial greeting to the whole community, in advance thank you very much for your precious time
a general way I have the following, a package in which I have a main procedure which I recible three parameters: a start date, a final, and a number of client
to use the dates I enter as parameter to query yields no records, but if I assign the date internally in the procedure, if it sheds records, the strange thing is that both the data and the parameters that are identical internally assigned even in its length and I checked, the truth and I stay out of ideas thank you very much for your time attaching the code
for now I'm just using the second query forget the first
------call to procedure-----
DECLARE
errcode VARCHAR2(200);
errbuf VARCHAR2(200);
BEGIN
xxxxx.pkg.xxxinitial_end(errcode  ,errbuf
                                                    ,'2013/08/19 00:00:00'
                                                    ,'2013/08/23 00:00:00','456456456546');
END;
-----------------------------------------------------------------procedure---------------------------------------------------------------------
PROCEDURExxxinitial_end (ERRCODE OUT VARCHAR2
  , ERRBUFF OUT VARCHAR2
  , p_initial_date IN VARCHAR2
  , p_end_date IN VARCHAR2
  , customer IN VARCHAR2)IS
l_encoding_line VARCHAR2(240);
cur_without_customer SYS_REFCURSOR;
cur_with_customer SYS_REFCURSOR;
  initial_date DATE;
  end_date DATE;
  initial_date2 DATE;
  end_date2 DATE;
BEGIN
l_encoding_line := '<?xml version="1.0" encoding=' || '"iso-8859-1"' ||
                   ' ?>' || chr(10) || '<XXOCS_TOTAL_VENTAS_SINEXP>';
  initial_date := to_date(p_initial_date, 'YYYY/MM/DD HH24:MI:SS');-----------------input parameters  NOT WORKING
  end_date := to_date(p_end_date, 'YYYY/MM/DD HH24:MI:SS');-------------------input parameters
  initial_date2:=to_date('2013/08/19 00:00:00', 'YYYY/MM/DD HH24:MI:SS');---------------------default values
  end_date2:=to_date('2013/08/23 00:00:00', 'YYYY/MM/DD HH24:MI:SS');---------------------default values        WORKING FINE
  IF customer IS NULL THEN
   -- OPEN cur_without_customer;
    DBMS_OUTPUT.PUT_LINE('se ejecuto el primero');
    -------------------------cursor  -----------------------------------
    OPEN cur_without_customer FOR
        SELECT rct.customer_trx_id
              ,rctl.customer_trx_line_id
              ,hp.party_name ---cliente
              ,hca.account_number ----N° Cliente
              ,rctl.line_number -----item
              ,rctt.name---descripcion transaccion
              ,rct.trx_number -----numero
              ,rctt.type ------tipo de transaccion
              ,hp.party_id--control solamente
              ,rct.trx_date------Fecha de emisión Comprobante de Venta
              ,rct.attribute1   ---No. de autorización del Comprobante de Venta
              ,mp.attribute9||rct.trx_number N_Comprobante---No. de Comprobante de Venta
              ,rct.attribute4-----Unidad Estratégica de Negocio
              ,mp.attribute9----  N° de establecimiento
              ,rctl.description-----Descripción (Tipo de Combustible)
              ,rctl.quantity_invoiced---Cantidad Vendida en galones
              ,rctl.unit_selling_price---Precio de venta unitario
              --,rctl.taxable_amount-------Valor Base Imponible --restriccion
              --,rctl.extended_amount---valor iva 12%
             -- ,NVL(importe_12(rctl.customer_trx_line_id,rct.customer_trx_id),'N/A')
          FROM ra_customer_trx_all         rct,
               ra_customer_trx_lines_all   rctl,
               hz_cust_accounts            hca,
               hz_parties                  hp,
               ra_cust_trx_types_all       rctt,
               mtl_parameters              mp
              -- mtl_system_items_b          msi,
             --  zx_lines                    zl
               --ra_batch_sources_all  rbs
         WHERE
           --rct.trx_date BETWEEN initial_date  AND end_date --parametros de fecha
           rct.trx_date BETWEEN to_date('2013/08/19 00:00:00', 'YYYY/MM/DD HH24:MI:SS')/*initial_date*/ AND to_date('2013/08/23 00:00:00', 'YYYY/MM/DD HH24:MI:SS')/*end_date*/
           AND rct.sold_to_customer_id = hca.cust_account_id
           AND hca.party_id = hp.party_id
           AND rct.customer_trx_id=rctl.customer_trx_id
           --AND rctl.inventory_item_id=msi.inventory_item_id
           AND mp.organization_id=rctl.warehouse_id
           AND rct.cust_trx_type_id = rctt.cust_trx_type_id;
     print_output(fnd_file.output, l_encoding_line);
    get_xml(cur_without_customer, 'G_REGISTER', 'CABECERA', ERRCODE);                         
  IF ERRCODE = 1 THEN
    ERRBUFF := 'El reporte no arrojo datos para los parametros ingresados';
    ERRCODE := 2;
    RETURN;
  ELSIF ERRCODE = 2 THEN
    ERRBUFF := SQLERRM;
    RETURN;
  END IF;
  print_output(fnd_file.output, '</XXOCS_TOTAL_VENTAS_SINEXP>');
     ELSE
     --  OPEN cur_with_customer;
       DBMS_OUTPUT.PUT_LINE('se ejecuto el segundo');
       -----------------------cursor 2---------------------------
       DBMS_OUTPUT.PUT_LINE('customer ' || customer);
       DBMS_OUTPUT.PUT_LINE('ASI ESTAN ENTRANDO LOS PARAMETROS              '||length(p_initial_date));
       DBMS_OUTPUT.PUT_LINE('ASI ESTAN ENTRANDO LOS PARAMETROS              '||length(p_end_date));
       DBMS_OUTPUT.PUT_LINE('customer ' || customer);
       DBMS_OUTPUT.PUT_LINE('ASI ESTAN ENTRANDO LOS PARAMETROS   quemados   '|| length(initial_date2));
       DBMS_OUTPUT.PUT_LINE('ASI ESTAN ENTRANDO LOS PARAMETROS   quemados   '|| length(end_date2));
       DBMS_OUTPUT.PUT_LINE('customer ' || customer);
       DBMS_OUTPUT.PUT_LINE('ASI ESTAN ENTRANDO LOS PARAMETROS convertidso  '|| length(initial_date));
       DBMS_OUTPUT.PUT_LINE('ASI ESTAN ENTRANDO LOS PARAMETROS convertidos  '|| length(end_date));
       OPEN  cur_with_customer FOR
      SELECT     rct.customer_trx_id
                ,rctl.customer_trx_line_id
                ,hp.party_name ---cliente
                ,hca.account_number ----N° Cliente
                ,rctl.line_number-----item
                ,rctt.name---descripcion transaccion
                ,rct.trx_number -----numero
                ,rctt.type ------tipo de transaccion
                ,hp.party_id---control solamente
                ,rct.trx_date------Fecha de emisión Comprobante de Venta
                ,rct.attribute1   ---No. de autorización del Comprobante de Venta
                ,mp.attribute9||rct.trx_number N_Comprobante--No. de Comprobante de Venta
                ,rct.attribute4------ Unidad Estratégica de Negocio
                ,mp.attribute9---------N° de establecimiento
                ,rctl.description---------Descripción (Tipo de Combustible)
                ,rctl.quantity_invoiced----Cantidad Vendida en galones
                ,rctl.unit_selling_price ---Precio de venta unitario
               -- ,rctl.taxable_amount-------Valor Base Imponible --restriccion
               -- ,rctl.extended_amount---valor iva 12%
          -- ,NVL(importe_12(rctl.customer_trx_line_id,rct.customer_trx_id),'N/A')
            FROM ra_customer_trx_all           rct,
                 ra_customer_trx_lines_all     rctl,
                 hz_cust_accounts              hca,
                 hz_parties                    hp,
                 ra_cust_trx_types_all         rctt,
                 mtl_parameters                mp
                -- mtl_system_items_b            msi,
                 --zx_lines                      zl
             WHERE hca.account_number=customer
              AND  hca.party_id=hp.party_id
              AND  hca.cust_account_id=rct.sold_to_customer_id
              AND  rct.customer_trx_id=rctl.customer_trx_id
             -- AND  rctl.inventory_item_id=msi.inventory_item_id
              AND  mp.organization_id=rctl.warehouse_id
              AND  rct.cust_trx_type_id = rctt.cust_trx_type_id
              AND rownum = 1
        AND rct.trx_date BETWEEN initial_date AND end_date;<------------when I assign these parameters( initial_date AND end_date  )--are the insert by parameter  initial_date2 AND end_date2 defualt
       DBMS_OUTPUT.PUT_LINE('customer ' || customer);
       DBMS_OUTPUT.PUT_LINE('fe inicial ' || initial_date);
       DBMS_OUTPUT.PUT_LINE('fe final ' ||end_date);
       print_output(fnd_file.output, l_encoding_line);
       get_xml(cur_with_customer, 'G_REGISTER', 'CABECERA', ERRCODE);                         
  IF ERRCODE = 1 THEN
    ERRBUFF := 'El reporte no arrojo datos para los parametros ingresados';
    ERRCODE := 2;
    RETURN;
  ELSIF ERRCODE = 2 THEN
    ERRBUFF := SQLERRM;
    RETURN;
  END IF;
  print_output(fnd_file.output, '</XXOCS_TOTAL_VENTAS_SINEXP>');
    END IF;
    EXCEPTION
  WHEN OTHERS THEN
    print_output(fnd_file.log, 'Error Ventas sin Exportaciones:' || SQLERRM);
    ERRCODE := 2;
    ERRBUFF := SQLERRM;
  -- Initialization
END  xxxinitial_end;

Answer 1

Welcome.  As a note, this question has nothing to do with PL/SQL XML programming and everything to do with SQL and PL/SQL
That said, the simple test case I setup, because I don't have all your tables, works just fine.
declare
   l_errcode  VARCHAR2(300);
   l_errbuff  VARCHAR2(300);
   PROCEDURE xxxinitial_end (ERRCODE OUT VARCHAR2
     , ERRBUFF OUT VARCHAR2
     , p_initial_date IN VARCHAR2  -- why not a date?
     , p_end_date IN VARCHAR2      -- why not a date?
     , customer IN VARCHAR2)
   IS
     initial_date DATE;
     end_date DATE;
     l_value  VARCHAR2(10);
   BEGIN
     initial_date := to_date(p_initial_date, 'YYYY/MM/DD HH24:MI:SS');
     end_date := to_date(p_end_date, 'YYYY/MM/DD HH24:MI:SS');
     -- Not trapping the No Data Found on purpose
     SELECT 'hit'
       INTO l_value
       FROM dual
      WHERE SYSDATE BETWEEN initial_date AND end_date;
   END  xxxinitial_end;
begin
  -- Test statements here
  xxxinitial_end(l_errcode, l_errbuff
                 ,'2013/08/19 00:00:00'
                 ,'2013/10/19 00:00:00'
                 ,null);
end;
As a comment above says, if you are dealing with dates, why not use a DATE parameter in the procedure and avoid the conversion in your code.
Also, you can simplify your code a bit by using a third sys_refcursor and setting one of the opened cursors to it.  This allows you to pull out the common logic following the OPEN and only have one copy of it.
PROCEDURE xxxinitial_end (ERRCODE OUT VARCHAR2
  , ERRBUFF OUT VARCHAR2
  , p_initial_date IN VARCHAR2  -- why not a date?
  , p_end_date IN VARCHAR2      -- why not a date?
  , customer IN VARCHAR2)
IS
  l_encoding_line VARCHAR2(240);
  cur_without_customer SYS_REFCURSOR;
  cur_with_customer SYS_REFCURSOR;
  cur_comm          SYS_REFCURSOR;
  initial_date DATE;
  end_date DATE;
BEGIN
  l_encoding_line := '<?xml version="1.0" encoding=' || '"iso-8859-1"' ||
                     ' ?>' || chr(10) || '<XXOCS_TOTAL_VENTAS_SINEXP>';
  initial_date := to_date(p_initial_date, 'YYYY/MM/DD HH24:MI:SS');-----------------input parameters  NOT WORKING
  end_date := to_date(p_end_date, 'YYYY/MM/DD HH24:MI:SS');-------------------input parameters
  IF customer IS NULL THEN
    -------------------------cursor  -----------------------------------
    OPEN cur_without_customer FOR
        SELECT rct.customer_trx_id
              ,rctl.customer_trx_line_id
              ,hp.party_name ---cliente
              ,hca.account_number ----N° Cliente
              ,rctl.line_number -----item
              ,rctt.name---descripcion transaccion
              ,rct.trx_number -----numero
              ,rctt.type ------tipo de transaccion
              ,hp.party_id--control solamente
              ,rct.trx_date------Fecha de emisión Comprobante de Venta
              ,rct.attribute1   ---No. de autorización del Comprobante de Venta
              ,mp.attribute9||rct.trx_number N_Comprobante---No. de Comprobante de Venta
              ,rct.attribute4-----Unidad Estratégica de Negocio
              ,mp.attribute9----  N° de establecimiento
              ,rctl.description-----Descripción (Tipo de Combustible)
              ,rctl.quantity_invoiced---Cantidad Vendida en galones
              ,rctl.unit_selling_price---Precio de venta unitario
              --,rctl.taxable_amount-------Valor Base Imponible --restriccion
              --,rctl.extended_amount---valor iva 12%
             -- ,NVL(importe_12(rctl.customer_trx_line_id,rct.customer_trx_id),'N/A')
          FROM ra_customer_trx_all         rct,
               ra_customer_trx_lines_all   rctl,
               hz_cust_accounts            hca,
               hz_parties                  hp,
               ra_cust_trx_types_all       rctt,
               mtl_parameters              mp
              -- mtl_system_items_b          msi,
             --  zx_lines                    zl
               --ra_batch_sources_all  rbs
         WHERE
           --rct.trx_date BETWEEN initial_date  AND end_date --parametros de fecha
           rct.trx_date BETWEEN to_date('2013/08/19 00:00:00', 'YYYY/MM/DD HH24:MI:SS')/*initial_date*/ AND to_date('2013/08/23 00:00:00', 'YYYY/MM/DD HH24:MI:SS')/*end_date*/
           AND rct.sold_to_customer_id = hca.cust_account_id
           AND hca.party_id = hp.party_id
           AND rct.customer_trx_id=rctl.customer_trx_id
           --AND rctl.inventory_item_id=msi.inventory_item_id
           AND mp.organization_id=rctl.warehouse_id
           AND rct.cust_trx_type_id = rctt.cust_trx_type_id;
       cur_comm := cur_without_customer;
     ELSE
       -----------------------cursor 2---------------------------
       OPEN  cur_with_customer FOR
      SELECT     rct.customer_trx_id
                ,rctl.customer_trx_line_id
                ,hp.party_name ---cliente
                ,hca.account_number ----N° Cliente
                ,rctl.line_number-----item
                ,rctt.name---descripcion transaccion
                ,rct.trx_number -----numero
                ,rctt.type ------tipo de transaccion
                ,hp.party_id---control solamente
                ,rct.trx_date------Fecha de emisión Comprobante de Venta
                ,rct.attribute1   ---No. de autorización del Comprobante de Venta
                ,mp.attribute9||rct.trx_number N_Comprobante--No. de Comprobante de Venta
                ,rct.attribute4------ Unidad Estratégica de Negocio
                ,mp.attribute9---------N° de establecimiento
                ,rctl.description---------Descripción (Tipo de Combustible)
                ,rctl.quantity_invoiced----Cantidad Vendida en galones
                ,rctl.unit_selling_price ---Precio de venta unitario
               -- ,rctl.taxable_amount-------Valor Base Imponible --restriccion
               -- ,rctl.extended_amount---valor iva 12%
          -- ,NVL(importe_12(rctl.customer_trx_line_id,rct.customer_trx_id),'N/A')
            FROM ra_customer_trx_all           rct,
                 ra_customer_trx_lines_all     rctl,
                 hz_cust_accounts              hca,
                 hz_parties                    hp,
                 ra_cust_trx_types_all         rctt,
                 mtl_parameters                mp
                -- mtl_system_items_b            msi,
                 --zx_lines                      zl
             WHERE hca.account_number=customer
              AND  hca.party_id=hp.party_id
              AND  hca.cust_account_id=rct.sold_to_customer_id
              AND  rct.customer_trx_id=rctl.customer_trx_id
             -- AND  rctl.inventory_item_id=msi.inventory_item_id
              AND  mp.organization_id=rctl.warehouse_id
              AND  rct.cust_trx_type_id = rctt.cust_trx_type_id
              AND rownum = 1
        AND rct.trx_date BETWEEN initial_date AND end_date;<------------when I assign these parameters( initial_date AND end_date  )--are the insert by parameter  initial_date2 AND end_date2 defualt
     cur_comm := cur_with_customer;
  END IF;
  print_output(fnd_file.output, l_encoding_line);
  get_xml(cur_comm, 'G_REGISTER', 'CABECERA', ERRCODE);
  CLOSE cur_comm;
  IF ERRCODE = 1 THEN
    ERRBUFF := 'El reporte no arrojo datos para los parametros ingresados';
    ERRCODE := 2;
    RETURN;
  ELSIF ERRCODE = 2 THEN
    ERRBUFF := SQLERRM;
    RETURN;
  END IF;
EXCEPTION
  WHEN OTHERS THEN
    print_output(fnd_file.log, 'Error Ventas sin Exportaciones:' || SQLERRM);
    ERRCODE := 2;
    ERRBUFF := SQLERRM;
  -- Initialization
END  xxxinitial_end;