A Study To Assess GW677954 Used In Combination With Insulin In Subjects Who Have Type 2 Diabetes Mellitus

Inclusion criteria: * Have been diagnosed by a doctor with Type 2 Diabetes Mellitus at least 3 months before Screening * Have a body mass index within range 25 to 40.0kg/m2 inclusive * Females who meet above criteria must be physiologically incapable of becoming pregnant (ie., surgically sterilized, or post-menopausal per protocol definition) Exclusion criteria: * Significant weight loss or gain in the 3 months before screening * Have used insulin to treat hyperglycemia within 3 months before screening * Have a history of fluid retention * Have uncontrolled high blood pressure * Have liver disease * Take loop diuretics (water pills), certain blood thinners, and/or St. Johns Wort. - Have or have had certain kinds of cancer