WWW- A Boy Scout big shot has been caught with a stash of kiddie porn – graphic photos of young boys he swapped with other cyber-smut collectors, authorities revealed yesterday.

Douglas Smith, 61, who was national director of programs at Boy Scouts of America headquarters in Texas, is expected to plead guilty in federal court today.

His arrest was a blow to the 95-year-old organization, which had its offices raided three weeks ago by federal agents seeking Smith’s computer.

“We’re really shocked and disappointed because he had been a good employee,” said Greg Shields, a spokesman for the scouts.

“When we learned of the investigation, we put him on administrative leave, and a few days after he chose to retire.”

In addition to overseeing all of the boy scouts’ programs in churches and schools, Smith ran a task force dedicated to protecting youngsters from sexual predators.

At the same time, the married father of two was allegedly trafficking in sexually explicit photos of children having oral sex and intercourse, according to court documents.

“Many, if not all, of the children in the photos were boys,” a law enforcement source said.

None of the children in the pictures were boy scouts, and Smith did not have day-to-day contact with minors as part of his job, officials stressed.

His lawyer, Jack Strickland, said his client was devastated.

“I’ve got to tell you, this is a good man, and I would hate to see the entirety of his life and the good things he’s done defined by one incident,” he said.

Smith, who became an eagle scout as a youth – scouting’s highest achievement – decided to plead guilty without any agreement in place that would give him a break on his sentence.

“He has been very contrite, and he wants to do the right thing and get it behind him,” a source said.

In his Colleyville, Tex., neighborhood, parents were appalled by the allegations.

“Three weeks ago, my children said the FBI was in the neighborhood, and I told them they were crazy,” one mother said.

“I can’t figure out what’s more disturbing – that it’s happened or that they hadn’t told us about it until now.”

Smith worked for the boy scouts, which has 3.4 million members nationwide, for 39 years and he had a high-ranking job at headquarters since 1996, officials said.

Just five months ago, he wrote a letter to a legal magazine blasting opponents of the boy scouts’ ban on gay scout leaders.

“Some intolerant elements in our society want to force scouting to abandon its values and to become fundamentally different,” he wrote.

The boy scouts’ ban on gay leaders was upheld on free speech grounds by the Supreme Court in 2000.

“What’s sad is that the boy scouts continues to exclude very moral adults who want to be involved in the program, people who were kicked out after years solely because they’re gay and not because they did anything wrong,” said James Davidson, legal director of the Lambda Legal Defense and Education Fund, which fought the ban.

“Meanwhile, they’re putting people in key positions who did do something wrong.”