Immunogenicity, Reactogenicity and Safety Study of Two Different Formulations of GSK Biologicals' Human Rotavirus Vaccine, Rotarix, in Healthy Infants

Inclusion Criteria: * Subjects' parent(s)/ Legally Acceptable Representative (s) \[LAR(s)\] who, in the opinion of the investigator, can and will comply, with the requirements of the protocol. * Written informed consent obtained from the parent(s)/ LAR(s) of the subject prior to performing any study specific procedure. * A male or female between, and including, 6 and 10 weeks of age at the time of the first vaccination. * Healthy subjects as established by medical history and clinical examination before entering into the study. * Birth weight \>2000 grams. Exclusion Criteria: * Child in care. * Use of any investigational or non-registered product other than the study vaccines during the period starting 30 days before the first dose of study vaccine (Day-29 to Day 1), or planned use during the study period. * Chronic administration (defined as more than 14 days in total) of immunosuppressants or other immune-modifying drugs since birth. For corticosteroids, this will mean prednisone 0.5 mg/kg/day, or equivalent. Inhaled and topical steroids are allowed. * Administration of any chronic drug therapy to be continued during the study period. * Planned administration/administration of a vaccine not foreseen by the study protocol in the period starting 30 days before the first dose of vaccine administration and ending at Visit 3; with the exception of the inactivated influenza vaccine, which is allowed at any time during the study, and other licensed routine childhood vaccinations, according to the local immunization practice. * Concurrently participating in another clinical study, at any time during the study period, in which the subject has been or will be exposed to an investigational or a non-investigational product. * History of confirmed RV GE. * Previous vaccination against RV. * Any confirmed or suspected immunosuppressive or immunodeficient condition, (including Severe Combined Immunodeficiency \[SCID\] disorder) based on medical history and physical examination. * Uncorrected congenital malformation (such as Meckel's diverticulum) of the gastrointestinal tract that would predispose for Intussusception (IS). * History of IS. * Very prematurely born infants (born ≤28 weeks of gestation). * Hypersensitivity to latex. * Family history of congenital or hereditary immunodeficiency. * History of any reaction or hypersensitivity likely to be exacerbated by any component of the vaccine. * Major congenital defects or serious chronic illness. * History of any neurological disorders or seizures. * Acute disease and/or fever at the time of enrolment. This warrants deferral of vaccination. * Fever is defined as temperature ≥38.0°C/100.4°F. The preferred location for measuring temperature in this study will be the oral cavity, the axilla or the rectum. * Subjects with a minor illness (such as mild diarrhea, mild upper respiratory infection) without fever may, be enrolled at the discretion of the investigator. * Acute or chronic, clinically significant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by physical examination or medical history. * Administration of immunoglobulins and/or any blood products since birth or planned administration during the study period. * Administration of long-acting immune-modifying drugs at any time during the study period (e.g., infliximab). * GE within 7 days preceding the study vaccine administration (warrants deferral of the vaccination).