This primary objective of this Phase 1/2 study is to evaluate the DLT and MTD of escalating oral doses of ABT-751 given BID on Day 1 of each cycle for 7 days in combination with carboplatin given on a 21-day schedule. The carboplatin dose is fixed at AUC 6 and will be administered on Day 4 during the first cycle to facilitate the pharmacokinetic analysis. During the subsequent cycles both agents will be administered on Day 1. ABT-751 is administered at the following dose levels using the Simon rapid dose escalation model: 100, mg, 125 mg, 150 mg, 175 mg and 200 mg BID.