5. Prior therapy with Velcade is allowed as long as the patient had at least a PR to prior Velcade therapy, was not removed from Velcade therapy due to toxicity, and will have at least a 6 month Velcade treatment-free interval from last dose received until first study treatment. (Patients may receive maintenance therapy with drugs that are not in the proteasome inhibitor class during this 6 month Velcade treatment-free interval).