A racially tinged comment, uttered by an apparently inebriated Imette St. Guillen, may have sent bouncer Darryl Littlejohn into a murderous rage, detectives now believe, according to police sources. Just before Littlejohn was ordered to escort St. Guillen out of The Falls, a SoHo bar, on the night she was raped and killed, she told him: "That's why all you black people are in jail," witnesses told police. The remark came after a brief, contentious discussion with Littlejohn, police sources said..