The purpose of this study is to measure how safe eflornithine is in combination with temozolomide in patients with newly diagnosed glioblastoma multiforme (GBM) following radiation therapy. Safety and tolerability will be determined on the basis of physical exams, laboratory tests, and questions about any problems you might experience during the study.This study will also measure levels of eflornithine in patients following dosing, and it will evaluate how effective eflornithine is as a treatment of GBM when combined with temozolomide. Eflornithine is an experimental drug, which means that it...