The four men indicted on charges of a terrorist plot to blow up two Riverdale synagogues and shoot down military planes were arraigned today, pleading not guilty in a Westchester courtroom. Before the judge arrived, one of the defendants, Laguerre Payen, had to be removed from the court when his baggy pants fell down, exposing his boxer shorts. The Haitian-born Payen is a diagnosed schizophrenic, whose attorney said that he is illiterate and does not understand the charges against him. Payen told the judge, "I don't understand, like the stuff the courts talk about." A federal prosecutor said that Payen's behavior is an act, telling the court, "On April 28th, he is on a very clear recording talking about beating the case in a very sophisticated way. It's very different from the way he's talking now in an effort to mislead the court." The four men face life in prison if they are convicted of the eight-count indictment.