  The data on the charge-exchange reaction K^+Xe --> K^0 p Xe, obtained with
the bubble chamber DIANA, are reanalyzed using increased statistics and updated
selections. Our previous evidence for formation of a narrow pK^0 resonance with
mass near 1538 MeV is confirmed and reinforced. The statistical significance of
the signal reaches some 8\sigma (6\sigma) when estimated as S/\sqrt{B}
(S/\sqrt{B+S}). The mass and intrinsic width of the \Theta^+ baryon are
measured as m = (1538+-2) MeV and \Gamma = (0.39+-0.10) MeV.
