John Newman felt like a criminal. The former Vallejo grade school teacher idled his R.V. at the Canadian border waiting to cross into the United States, nervous that at any moment customs agents would find his stash of drugs.

He had taken precautions?his pharmacist had put the pills in plain brown bottles. ?He said, ?If you get caught, tell them they?re for chemotherapy,?? Mr. Newman recalled. The drugs were actually life-saving medications to treat Mr. Newman?s H.I.V. But for 22 years, H.I.V.-positive foreigners were banned from entering the United States.