Unquenched simulations with N_f=2 light quark flavours

The quark mass dependence of meson masses and decay constants in N_f=2 QCD is studied at a fixed gauge coupling with different dynamical quark masses. Partially Quenched Wilson Chiral Perturbation Theory (PQWchiPT) is applied to obtain the extrapolation to zero quark mass. It is shown, that in our analysis NNLO-terms play a more important role than O(a)-terms, which can be neglected. Also we compare our results with recent CP-PACS results.