The purpose of this study is to evaluate the safety and effectiveness of RCV (Racivir®) when used together with other HIV drugs in people who have previously been treated with 3TC (lamivudine, Epivir®) and are failing with their current HAART treatments. This study will include a total of 60 HIV infected, HAART-experienced subjects currently receiving 3TC (lamivudine, Epivir®) as part of their HAART therapy. The study will take place at approximately 11 study sites in the US and Latin America.