  We present an analysis of XMM-Newton X-ray data of WR30a (WO+O), a close
massive binary that harbours an oxygen-rich Wolf-Rayet star. Its spectrum is
characterized by the presence of two well-separated broad peaks, or `bumps',
one peaking at energies between 1 and 2 keV and the other between 5 and 7 keV.
A two-component model is required to match the observed spectrum. The higher
energy spectral peak is considerably more absorbed and dominates the X-ray
luminosity. For the currently accepted distance of 7.77 kpc, the X-ray
luminosity of WR30a is L_X > 10^{34} erg s^{-1}, making it one of the most
X-ray luminous WR+O binary amongst those in the Galaxy with orbital periods
less than ~20 d. The X-ray spectrum can be acceptably fitted using either
thermal or nonthermal models, so the X-ray production mechanism is yet unclear.
