HARARE (AFP) — Robert Mugabe was sworn in Sunday for a sixth term of office as Zimbabwe president after being declared winner of a one-man election widely denounced throughout the world as an illegitimate farce. "I will well and truly serve this country in the office of president, so help me God," 84-year-old Mugabe said at a ceremony at his State House residence, presided over by Chief Justice Godfrey Chidyausiku.