If appearance matters, Hassan Abu-jihaad is an improbable holy warrior. His demeanor has been painfully meek during the legal proceedings leading up to his trial Monday in federal court in New Haven, where he is charged with transmitting military secrets to terrorists. Mostly, he has been a bewildered-looking man in an oversize prison jumpsuit.Little is known about him. He was born Paul R. Hall and lived in Southern California. He converted to Islam, changed his name and joined the Navy. Later, he would be recorded by the FBI laughing with a friend at an al-Qaida propaganda video showing an insurgent known as the Juba sniper killing American soldiers in Iraq. "They show him knocking out about Â… probably like, 10 of 'em," says the friend, who confides to Abu-jihaad that he screened the video with a girlfriend. "Ding! Ding! Ding! I'm like, Allahu Akbar."