We present analysis of the XMM-Newton spectrum of the radio-loud narrow-line
quasar 3C 234. The ultra-flat (Gamma~0.08) X-ray continuum measured by ASCA is
shown to be the result of heavy absorption with Nh>10e23 cm-2. The soft X-ray
emission is dominated by a wealth of emission lines as usually observed in
most of low-luminosity obscured AGN. We also report the discovery of a narrow
Fe K line at 6.4 keV (EW~200 eV). 3C 234 therefore appears as one of the best
examples of a genuine "big cousin" of a Seyfert 2 galaxy observed so far.
Furthermore, the XMM-Newton image reveals the remarkable presence of X-ray
emission associated with the radio jet  extending ~120 kpc from the nucleus.