This is a long-term follow-up study at Years 11, 12, 13, 14 and 15 after primary vaccination with GSK Biologicals' hepatitis A/hepatitis B vaccine (three-dose schedule, 3 different lots). To evaluate the long-term antibody persistence, volunteers will be bled at Years 11, 12, 13, 14 and 15 after the first vaccine dose of the primary vaccination course to determine their anti-HAV and anti-HBs antibody concentrations.