  We study the pulsational stability of the rapidly rotating Be star HD 163868
using a newly developed 2D oscillation code which takes the Coriolis force
fully into account and compare our results with observations (MOST) and recent
other stability analyses of this ~ 6 Msun star. We find both prograde and
retrograde overstable modes (although more prograde than retrograde modes) and
confirm the existence of low degree odd r-modes destabilised by the
kappa-mechanism. The ultra-low frequency modes that could not be explained in a
previous analysis are interpreted as high degree, retrograde m=1 modes. A
reasonably good fit to the observed oscillation spectrum is possible if we
assume that only even modes are observed. This requires a nearly equator-on
view of the observed star, consistent with the measured high v sin i value of
250 km/s.
