The present clinical study will assess the immunogenicity and reactogenicity of Aventis Pasteur's DTacP-IPV// PRP~T combined vaccine (Pentavac™ or Pentaxim™) as a three-dose primary vaccination at 6, 10 and 14 weeks of age followed by a booster dose during the second year of life in order to meet the requirements for application for the use of the product in the Expanded Program on Immunization (EPI) in South Africa.