00904. 00000 - "%s: invalid identifier" run a query correctly implemented

Hi,

I faced a strange problem during the migration from Oracle database version10.2.0.5 (old DB) to 11.2.0.4 (new DB).

The following query in the "old DB" works corretly:

SELECT a.*, b.customerid, b.contractid, c.transactionid

          FROM (SELECT SOURCE, ndgint, codspo, cancol, tipprd, numctr, codprd, famprd, abicco,

                       cabcco, numcco, datope, datchi, stactr, codiv, impdiv, impeur, datarif,

                       codsoc, codprdcol, codrap, tipprdold, tipfir, rapsgr, codcolhor, tag,

                       DECODE (appl, hor.c_appl_pwm, hor.c_appl_pbb, appl) AS appl,

                       NVL (cc.classe_clientela, 0) AS codclacli, recid AS rec_id, row_id,

                       CASE

                           WHEN appl = x_appl_hor

                               THEN hor.c_institute_hor

                           WHEN appl = hor.c_appl_pbb