implicit conversion in 11g

The below query is not working in 11.2.0.4 and the same works fine in all 10.2.0.4 environments. If we put TO_CHAR for (store.store) it works fine.

We have some 1000's of objects having this kind of queries.

   select distinct addr.country_id

        from store, store_hierarchy, wh_ext, wh, csi_uda_lov, addr

        where store.store = store_hierarchy.store

        and store_hierarchy.chain = 1

        and store.store = csi_uda_lov.store_num

        and csi_uda_lov.csi_uda_gid = 3306

        and store.default_wh = wh.wh

        and wh.physical_wh = wh_ext.wh

        and wh_ext.dc_cd = substr('US1BU',1,3)

        and addr.key_value_1 = store.store -- Existing