A Study to Investigate the Tolerability and Safety of Converting Stable Renal Transplant Recipients Who Receive Tacrolimus With or Without Corticosteroids From Mycophenolate Mofetil (MMF) to Enteric-coated Mycophenolate Sodium (EC-MPS)

Inclusion criteria: * Recipients of first or secondary cadaveric heart-beating, living unrelated or living related kidney transplant. * Currently receiving 1, 1.5, or 2 g MMF/day, tacrolimus with or without corticosteroids as part of their immunosuppressive regimen for at least 3 months. * In a stable condition in terms of graft function. Exclusion criteria: * Patients who had taken an investigational drug within four weeks prior to study entry * History of malignancy within the last 5 years, except excised squamous or basal cell carcinoma of the skin. * Thrombocytopenia (\<75,000/mm3), with an absolute neutrophil count of \<1,500/mm3 and/or leukocytopenia (\<2,500/mm3), and/or hemoglobin \<6.0 g/dL prior to enrollment * Clinically significant infection requiring continued therapy, severe diarrhea, active peptic ulcer disease, or uncontrolled diabetes mellitus, evidence of severe liver disease, HIV or Hepatitis B surface antigen positive. Other protocol-defined inclusion/exclusion criteria may apply.