Study Combining Imatinib Mesylate (Gleevec) With Sorafenib in Patients With Androgen-independent Prostate Cancer (AIPC)

Eligible patients will be enrolled in one of 4 cohorts where each cohort will allow 3 patients to be on study. Patients will receive both study drugs on escalated dosing schedule until the maximum of 400 mg PO BID is reached for both drugs or toxicity is established. Once the pre-specified 400 mg by mouth two times a day (PO BID) dosing for both drugs is reached without toxicity, the study will close for accrual. If toxicity is noted prior to reaching the 400 mg PO BID dosing, then the dosing schedule that is deemed safest as per study design will be the one used for any future phase II study.