  Aims. The properties of the Galactic supernova remnant (SNR) RX J0852.0-4622
are theoretically analysed.
  Methods. An explicitly time-dependent, nonlinear kinetic model of cosmic ray
(CR) acceleration in SNRs is used to describe the properties of SNR RX
J0852.0-4622, the accelerated CRs and the nonthermal emission. The source is
assumed to be at a distance of ~1 kpc in the wind bubble of a massive
progenitor star. An estimate of the thermal X-ray flux in such a configuration
is given.
  Results. We find that the overall synchrotron spectrum of RX J0852.0-4622 as
well as the filamentary structures in hard X-rays lead to an amplified magnetic
field B > 100 muG in the SNR interior. This implies that the leptonic very high
energy (VHE) gamma-ray emission is suppressed, and that the VHE gamma-rays are
hadronically dominated. The energy spectrum of protons produced over the
life-time of the remnant until now may well reach ''knee'' energies. The
derived gamma-ray morphology is consistent with the H.E.S.S. measurements. The
amount of energy in energetic particles corresponds to about 35% of the
hydrodynamic explosion energy. A remaining uncertainty concerns the thermal
X-ray flux at 1 keV. A rough estimate, possibly not quite appropriate for the
assumed wind bubble configuration, results in it being larger than the
nonthermal flux at this energy.
  Conclusions. It is concluded that this SNR expanding into the wind bubble of
a massive star in a dense gas environment can be a hadronic gamma-ray source
that is consistent with all existing multi-wavelength constraints, except
possibly the thermal X-ray emission.
