The purpose of this Phase 4 study is to assess the safety and immunogenicity of GSK's combined diphtheria, tetanus, acellular pertussis, hepatitis B, inactivated poliovirus and Haemophilus influenzae type b conjugate vaccine (DTPa-HBV-IPV/Hib) versus MCM Vaccine BV's DTaP5-HBV-IPV-Hib vaccine administered to 500 healthy infants and toddlers, between 6 and 12 weeks of age at the time of first vaccination, based on a 2-, 4-, and 12-months of age vaccination schedule.