  In a model recently proposed by Albrecht and Skordis it was suggested that
the observed accelerated expansion of the universe could be caused by a scalar
field which is trapped in a local minimum of an exponential potential modified
by a polynomial prefactor. We show that scalar field cosmologies with this kind
of local minimum in the potential are stable and do not decay to the true
vacuum if they fulfill the observational constraints from the Type Ia
Supernovae experiments. Further we briefly sketch how this potential could be
related to a potential of interacting D-branes.
