To assess the safety and immune response to two experimental vaccines when formulated with QS-21 or QS-21 plus alum. To determine whether the new preparation of QS-21 in polysorbate 80 is less reactogenic than the QS-21 formulation used in AVEG Protocols 016, 016A, and 016B. To examine whether QS-21 is immunologically equivalent to that used in 16B. To determine if QS-21, when given with low doses of antigen, induces measurable HIV-1-specific CTL activity. To evaluate if the QS-21 dose-sparing effect extends to an antigen dose of 0.5 micrograms. To determine if the bivalent vaccine gives responses equivalent to the monovalent product or if a broadening of the HIV-1-specific binding and neutralizing antibody responses occurs.