Six years after their last collaboration, Kimya Dawson and Stephan Jenkins will reunite for a bittersweet duet, 'Why Can't You Be,' which will appear on Third Eye Blind's forthcoming album, 'Ursa Major.' "We've known each other for a long time," Jenkins tells Spinner. "She has these different kinds of sounds that are very distinctive. One is this dreamy sound." That's the one Jenkins wanted for the song, a melancholic breakup story with a veneer of indifference, relayed in "he said, she said" mode.

"It's a song that came out of an argument with an ex-girlfriend," Jenkins explains. "It's perfect for Kimya's voice because there's something innocent and childlike in the way she sings. But she also gets down to the core of things. I'm a big Kimya fan. She's so legit. She's unique and the least affected person. She's kind of like a Kerouac character."

Long before she found household fame with the 'Juno' soundtrack, Jenkins invited the former Moldy Peaches singer to perform on his band's 2003 song, 'Self-Righteous.' "We are big fans of the Moldy Peaches," Jenkins says of Third Eye Blind. "Ours is an old relationship."

The pair started talking about getting together again last year. "She called me and said she wanted to quote one of my songs in something she was doing," Jenkins says. "I said, 'sure, and you can pay me by doing another duet with me.'" Dawson happily agreed.

Dawson toured with Third Eye Blind in 2003, singing 'Self-Righteous' with Jenkins, but plans to get together to perform 'Why Can't You Be' on Third Eye Blind's current tour have so far failed. "If we can make that happen," says Jenkins, "We will." In the meantime, 'Ursa Major' hits stores on August 18.