Bortezomib Plus Prednisone for Initial Therapy of Chronic Graft Versus Host Disease

* Each treatment cycle lasts five weeks, during which time participants will come to the clinic to receive bortezomib intravenously once a week for the first 4 weeks. Prednisone will be taken orally on a daily basis and dose reduction may be initiated after 1 cycle of therapy. * During all treatment cycles, participants will have the following: physical exam and blood work. At the end of cycle 3 (week 15) the participants cGVHD will be evaluated. These assessments may include an eye examination, a skin examination, a pulmonary function test and/or, a flexion assessment test. * Participants will receive 3 cycles of bortezomib.