In this study the investigators want to find out more about the efficacy of giving higher doses of radiation with concurrent chemotherapy in controlling unresectable pancreas cancers than are used in either the pre-operative or post-operative setting. The investigators will assess acute and late side effects (problems and symptoms) of radiation therapy given at these higher doses of radiation (dose escalated) following full dose chemotherapy given before the radiation and with concurrent chemotherapy for pancreas cancer. Radiation therapy is given in higher doses that are limited by the proximity of normal organs to the radiation dose distribution to improve the likelihood of controlling the tumor in the pancreas while minimizing the risk of radiation injury to these organs. There are two chemotherapy drugs, Capecitabine is an oral drug taken twice per day on the same day that radiation therapy is given and Gemcitabine is an intravenous drug given once per week, during radiation therapy. Everyone in this study will have already received chemotherapy alone first. Everyone in this study will receive radiation therapy and concurrent chemotherapy.