  In this paper, the problem of writing on a dirty paper in the presence of
jamming is examined. We consider an AWGN channel with an additive white
Gaussian state and an additive adversarial jammer. The state is assumed to be
known non-causally to the encoder and the jammer but not to the decoder. The
capacity of the channel in the presence of a jammer is determined. A surprising
result that this capacity is equal to the capacity of a relaxed version of the
problem, where the state is also known non-causally to the decoder, is proved.
