Compare Immunogenicity & Safety of 2 Formulations of GSK Biologicals' DTPa-HBV-IPV/Hib Vaccine Given in Healthy Infants

"Inclusion criteria: * A healthy male or female infant between, and including, 11 and 17 weeks of age at the time of the first vaccination. * Infant born to known hepatitis B surface antigen (HBsAg) seronegative mother (documented laboratory result of HBsAg assay from the maternal blood sample is available). * Born after a normal gestation period (between 36 and 42 weeks). * Written informed consent obtained from the parent or guardian of the subject. Exclusion criteria: * Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine(s) within 30 days preceding the first dose of study vaccine, or planned use during the study period. * Chronic administration of immunosuppressants or other immune-modifying drugs within six months prior to the first vaccine dose. * Any chronic drug therapy to be continued during the study period. * Planned administration/ administration of a vaccine not foreseen by the study protocol during the period starting from 30 days before each dose of study vaccine and ending 30 days after the last vaccine dose. * Previous vaccination against diphtheria, tetanus, pertussis, poliomyelitis, hepatitis B and/or Haemophilus influenzae diseases. * Known history of or exposure to diphtheria, tetanus, pertussis, poliomyelitis, hepatitis B and/or Haemophilus influenzae diseases since birth. * History of allergic disease or reactions likely to be exacerbated by any component of the vaccines. "