Vanessa Hudgens Sued By Former Business Partner

It's a case of "sweet" gone sour for producer Johnny Vieira, who's suing High School Musical star Vanessa Hudgens.

In court papers filed Monday in Los Angeles County Superior Court and obtained by PEOPLE, Vieira is demanding more than $5 million and punitive damages from the Disney star.

Vieira claims that he and Hudgens, now 19, worked together to launch her career – and that they agreed to "share equally" in the profits. (Because the actress was a minor at the time, Vieira contends that a court approved the 2005 agreement.)

At one point, states the suit, which was first reported by TMZ.com, Hudgens sent a photo of herself to the producer, inscribing it: "Johnny, thank you for everything, without you, I would be no where, we will make it BIG – Vanessa Hudgens. Sweet."

But after High School Musical became a hit, he says she dumped him – and that she still owes him $2 million – which the documents for the suit state Vieira discovered "after an expensive audit."

There has been no comment from Hudgens's camp.