To compare three formulations of Hib-MenAC vaccines mixed with Tritanrix™-HepB vaccine with that of Tritanrix™-HepB vaccine concomitantly administered with GSK Biologicals' Hiberix™ vaccine and Tritanrix™-HepB vaccine mixed with Hiberix™ vaccine and concomitantly administered with Wyeth Lederle's meningococcal C conjugate vaccine (Meningitec™), with respect to antibody response to vaccine antigens (meningococcal serogroups A and C and PRP) after a three-dose primary vaccination course.

Randomized study with five groups to receive one of the following vaccination regimens: One of the three formulations of GSK Biologicals' Hib-MenAC mixed with GSK Biologicals' Tritanrix™-HepB (3 different groups) GSK Biologicals' Tritanrix™-HepB + GSK Biologicals' Hiberix™ GSK Biologicals' Tritanrix™-HepB mixed with GSK Biologicals' Hiberix™ + Wyeth Lederle's Meningitec™

Inclusion Criteria:

• Healthy infant between 6 and 10 weeks of age at the time of the first vaccination, written informed consent obtained from the parents, born after a gestation period of 36 to 42 weeks.

Exclusion criteria:

• Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine(s) or planned administration/ administration of vaccine not foreseen by the study protocol within 30 days preceding the first dose of study vaccine during study period, or planned use during study period with exception of oral polio vaccine (OPV).
• Chronic administration of immunosuppressants or other immune-modifying drugs since birth.
• Hepatitis B and Bacille Calmette-Guérin (BCG) vaccine received after the first 2 weeks of life.
• Any confirmed or suspected immunosuppressive or immunodeficient condition based on medical history and physical examination.
• Administration of immunoglobulins and/or any blood products since birth or planned administration during the study period.
• Previous vaccination against diphtheria, tetanus, pertussis, hepatitis B, Haemophilus influenzae type b, and/or meningococcal disease with the exception of a birth dose of hepatitis B vaccine.