  This paper proves one of the open problem posed by Beigi et al. in
arXiv:1004.0411v2. We consider quantum interactive proof systems where in the
beginning the verifier and prover send messages to each other with the combined
length of all messages being at most logarithmic (in the input length); and at
the end the prover sends a polynomial-length message to the verifier. We show
that this class has the same expressive power as QMA.
