SAN FRANCISCO, CA  [Friday Jul.6.2007]  /Mix103FM.com/ -- Antimusic.com reports that pop star Avril Lavigne is being sued over hit current hit single "Girlfriend."

Songwriters Dunbar and James Gangwer have alleged that parts of the track are a rip-off of a tune called "I Wanna Be Your Boyfriend," released by the Rubinoos in 1979.

San Francisco lawyer Nicholas Carlin said, "She's made a lot of money off of my client's song."

"The entire song is not the same, they have different bridges, but the heart and soul of her song is directly taken from our client's song."

Lavigne's manager says the suit is "baseless" and likened it to a "case of legal blackmail."

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