In the first case of its kind, an Army private court-martialed on charges of knowingly exposing three soldiers to the AIDS virus was found guilty of sodomy and discrediting the military. Pvt. Adrian Morris Jr. was found not guilty of three counts of aggravated assault and two other counts of bringing discredit to the military, according to verdicts handed down by Col. Raymond D. Cole, a military circuit judge. Cole sentenced Morris to a bad-conduct discharge, forfeiture of $400 a month in pay for three months and a two-month restriction to Ft. Huachuca in Arizona. He also gave Morris a direct order not to have unprotected sex with anyone. Morris, 28, of Caseyville, Ill., was the first person to be court-martialed on charges of exposing others to the AIDS virus.