  We consider a model with two real scalar fields which admits phantom domain
wall solutions. We investigate the structure and evolution of these phantom
domain walls in an expanding homogeneous and isotropic universe. In particular,
we show that the increase of the tension of the domain walls with cosmic time,
associated to the evolution of the phantom scalar field, is responsible for an
additional damping term in their equations of motion. We describe the
macroscopic dynamics of phantom domain walls, showing that extended phantom
defects whose tension varies on a cosmological timescale cannot be the dark
energy.
