Alan Jackson is a big fan of bluegrass music. Heck, he even recorded an album produced by bluegrass phenom Alison Krauss. He's also a fan of fellow singer Rhonda Vincent, another of the most popular and well-respected (not to mention most award-winning) women in bluegrass.

So, it's no surprise that Alan asked Rhonda to add harmonies to three of the songs on his upcoming album, 'Freight Train,' including the new single, 'It's Just That Way.' Yet, although he has always loved her voice, Alan tells Dial-Global there are some songs Rhonda refuses to help him out on, even though she's obviously a big fan of his music as well.

"Rhonda has sung harmony before with us and I've just always loved her. She's just one of the best to me -- can sing the bluegrass or she can sing country, either one. The only thing about Rhonda is if it's a drinkin' song, she won't sing on it."

While Alan says he respects the singer for that conviction, he's well aware that he's recorded more than a few tunes that would be off limits for her.

"You can't call her in on 'Good Time' or something ... it's 'I can't sing on that,' and I [say], 'OK.'

Alan's new 'Freight Train,' with Rhonda aboard for the non-drinking songs, pulls into the station on March 30.

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