BOSTON — Massachusetts Gov. Deval Patrick has fielded calls on hundreds of subjects during his monthly “Ask the Governor” radio show. But this call was one of a kind.

“Uh, Governor, this is Barack Obama, formerly of Somerville,” the caller began Thursday. “I’ve got a few complaints about service in and around the neighborhood, but I’ve moved down South since that time.”

The president was indeed calling in to WGBH-FM to congratulate Patrick, a friend and political ally who’s wrapping up two terms in office. Obama once lived in the Boston suburb of Somerville, while attending Harvard Law School.

Patrick sounded surprised and initially unconvinced that it really was Obama on the phone and not an impersonator. And he gently chided the president for a slight stumble in pronouncing the state’s name.