This is a non-randomized multicenter Phase II trial of Gleevec and docetaxel in chemo naïve metastatic hormone refractory prostate cancer. The primary objective of this study is to assess the time to disease progression in patients with hormone refractory prostate cancer treated with daily oral imatinib and intravenous docetaxel, administered every three weeks. Secondary objectives include: 1) to assess the rate of response to imatinib and docetaxel, using Prostate Specific Antigen (PSA) and/or measurable disease; 2) to assess the overall survival of patients with hormone refractory prostate cancer treated with imatinib and docetaxel; and 3) to evaluate the qualitative and quantitative toxicities of this combination.