NULL-Columns displayed as "0€" in reports graph

Hi,

since Upgrade to Report Builder Version 12.2.1.4 we got problem in all dynamic graphics in report builder.

NULL-columns displayed as "0€".

Query:

SELECT p.pe_persnr                                                     AS ktg_graph_persnr,

    'Nettoeinkommen'                                                  AS ktg_graph_daten,

    DECODE(:pers_einkommensart, 'SB', spack_lueckenberechnung.get_rente_nettoeink_sb(p.pe_persnr, 'N'), :pers_netto_mon) AS ktg_graph_gehalt,

    NULL                                                        AS ktg_graph_lohnfort

FROM personen p

UNION ALL

SELECT p.pe_persnr AS ktg_graph_persnr, 

    'Lohnfortzahlung' AS ktg_graph_daten, 

    NULL AS ktg_graph_gehalt,

    :pers_lueck_lohnfortzahl_z AS ktg_graph_lohnfort

FROM personen p

XML Graphic Settings:

<rw:graph id="CT_3" src="G_ktg_graph" groups="ktg_graph_daten" dataValues="ktg_graph_wert">