The purpose of this study is to test the effect of MK0941 as add-on therapy for patients taking insulin for Type 2 Diabetes.
Arm 1: MK0941 10 mg tablets TID. Arm 2: MK0941 20 mg tablets TID Arm 3: MK0941 30 mg tablets TID Arm 4: MK0941 40 mg tablets TID.