  The spectrum of orbitally excited $D_s$ mesons is computed in the continuum
limit of quenched lattice QCD. The results are consistent with the
interpretation that the narrow resonance in the $D_s \pi^0$ channel discovered
by the BABAR Collaboration is a $J^P=0^+$ $c\bar{s}$ meson. Furthermore, within
statistical errors, the $1^+-1^-$ and the $0^+-0^-$ mass splittings are equal,
in agreement with the chiral multiplet structure predicted by heavy hadron
chiral effective theory. On our coarsest lattice we present results from the
first study of orbitally excited $D_s$ mesons with two flavors of dynamical
quarks, with mass slightly larger than the strange quark mass. These results
are consistent with the quenched data.
