This study is a prospective, randomized, open label trial to compare the safety and efficacy of linagliptin (an oral anti diabetic medication) given orally once daily to an insulin regimen of glargine once daily plus rapid-acting insulin before meals. Both of these treatment groups will be given corrective doses of rapid-acting insulin analogs (aspart, lispro or glulisine) before meals if their blood sugars are > 140 mg/dl.