CONCORD, N.H. – A soldier who died of an apparent heart attack in Iraq this week was born with a heart condition that his parents said seemed to disappear during his childhood.

The death of Spc. Matthew Schneider, a Gorham, N.H., native who was found dead in his bunk in Ar Ramadi, was perplexing to his father because the soldier was in top shape.

“I spoke to him about five hours before he died, and he complained of nothing,” said Andrew Schneider, who lives in Kittery, Maine. “This was a kid cranking out 100 pushups, and he was proud of the miles he could run.”

The 6-foot, 175-pound soldier who easily passed his physical training and was given a clean bill of health when he entered the Army was unresponsive in his bunk Monday morning. He was rushed to a medical facility but could not be revived.

His mother, Cynthia Tardiff, who now lives in Lunenberg, Vt., said her son was born with a condition that causes heart muscle to grow abnormally, but that it apparently had cleared up by the time Schneider was two years old.

The military is planning an autopsy and investigation into the death, which has delayed funeral arrangements, the soldier’s father said.

Schneider, 23, was assigned to the 141st Signal Battalion of the 1st Armored Division based in Wiesbaden, Germany.

“He was superhappy with his education and superhappy to serve in the armed forces,” Andrew Schneider said. The younger Schneider, who ran a communications station, had re-enlisted in the Army to train as a systems administrator.

Schneider was a 2001 graduate of Gorham High School and was well-liked by his teachers and classmates, according to Principal Keith Parent. Teachers said he excelled at computer skills and created a Web page for the students.

Schneider was one of the first students at the school involved in the Cisco Networking Academy, a program that provides training for students interested in the technology field.

He kept his passion for computers working at his father’s Internet company before reporting to duty in the Army.

He was remembered for more than his computer skills, though.

Assistant Principal Bill Kaczenski said faculty members recalled his thoughtfulness and his practical jokes as well as a knowledge of computers that surpassed most adults.

Schneider showed his computer skills – and his humor – by playing tricks on his fellow students. “There were a couple of times he’d freeze up people’s computers as a giggle-giggle ha-ha,” Kaczenski said.

Andrew Schneider said he has spoken twice to Maine Gov. John Baldacci, who’s assisting in burial arrangements at Arlington National Cemetery. It could be two or three weeks before the funeral is held, he said.