RUSUTSU, Japan  It would not be a G-8 without a microphone mishap.

When leaders of the world’s richest nations, the so-called Group of 8, gathered two years ago in St. Petersburg, Russia, President Bush was caught using some blunt, colorful language as he munched a roll during lunch. For four enlightening minutes, the world was treated to an unvarnished view of George W. Bush as he expounded on everything from his penchant for Diet Coke to his long-winded fellow leaders. (“I’m not going to talk too damn long like the rest of them.”)

At this week’s gathering on the northern Japanese island of Hokkaido, the lunchtime microphones were on again. The life-of-the-party president, mingling before the meal, chatted animatedly about his parents’ health, his birthday and the corruption charges facing one of his best buddies in Europe, Prime Minister Silvio Berlusconi of Italy.

“Amigo! Amigo!” Mr. Bush called out cheerily in Spanish when he spotted the Italian prime minister. “How you doing, Silvio? Good to see you!” Later, the president wondered about his former Russian counterpart, Vladimir V. Putin. “Did Putin come to see you since I saw you?” he asked Mr. Berlusconi. (He had not.)

Chancellor Angela Merkel of Germany walked in, clutching a newspaper featuring a photograph of the first President Bush during a recent trip to Berlin. “His father,” she noted to the other leaders, while President Bush looked concerned. The elder Bush, 84, has been slowing down since his hip replacement surgery last year.