SU011248 in Combination With Irinotecan and Cetuximab as a Second Line Regimen for Stage IV Colorectal Cancer

* Participants will be given a supply of SU011248 capsules to take at home in the morning for two weeks. After taking the capsules for two weeks, there will be a one-week rest period. * Irinotecan will be administered on days 1 and 8 of every 21-day cycle as an intravenous infusion over 90 minutes. Cetuximab will be administered intravenously on days 1, 8 and 15 of every 21-day cycle. The first treatment of cetuximab is a larger dose. Beginning with the second treatment, the participant will receive a smaller dose of cetuximab. * Blood work will be repeated at every clinic visit on days 1 and 8. During cycle 1, blood will also be drawn on day 15. * Tumor assessments will be repeated after 6 weeks, 12 weeks, and every 9 weeks thereafter, and will be assessed by both a CT scan of the abdomen, pelvis, and a chest x-ray. MUGA scans will be repeated every 4 cycles (12 weeks). * Participants may continue to receive cycles of study treatment as long as their disease does not progress and they do not experience any serious side effects.