An informal exorcism performed at the Cathedral of St. Paul this month was more profane than sacred and was directed toward gay Catholics, police and church authorities said Tuesday. They said the ritualistic sprinkling of blessed oil and salt around the church and in donation boxes amounted to costly vandalism and possibly even a hate crime. The damage was discovered Nov. 7 after the noon mass, and after words were exchanged between members of the Rainbow Sash Alliance, a gay rights group, and the opposing group, Catholics Against Sacrilege.