The comic actor has reportedly embarked on a relationship with Ali Hoffman and has been pals with her since they were young when they were growing up in Los Angeles.
A source told the New York Post newspaper: "They were friends when they were growing up. Jonah is good friends with Ali's brother Jake. Dustin discovered Jonah when they were in high school."
Things are going so well, Jonah - whose first big screen role was in 'I Heart Huckabees' which also starred Dustin - spent part of the festive season in Hawaii with Ali and her family.
The source added: "Jonah was in Hawaii over the holidays with the Hoffman clan."
Before Christmas, the 28-year-old actor revealed he is looking for a property in New York.
Jonah - who stars in new movie 'The Sitter, in which he plays an irresponsible babysitter - said: "I live in LA. I was born in LA. My folks are originally from New York, and I'm a first-generation Angeleno. I have friends there. A life there. But that town's too mellow. You can get wasted.
"So I'm looking for an apartment in New York. I feel happy there. There's constant excitement. So I'm hunting a place to live."