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Victoria Beckham is earning mixed reviews for her guest-judging stint on "American Idol." The erstwhile Posh Spice looked chic, if impossibly svelte, in a form-fitting strapless purple gown as she filled Paula Abdul's empty chair at auditions in Denver on Friday, but reports her singing critiques are being met with some harsh criticism of their own.

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"It didn't go too well," says a mole. "She tried too hard to be 'nice,' but came off as icy and wooden."

And somewhere, Paula does a happy dance with MC Skat Kat.

Adding to the alleged tryout hiccups: A number of "disappointed" contestants complained about Abdul not being there to offer her usual nonsensical pep talks.

Either way, the seemingly Stilted Spice says she's "beyond excited" to be stomping all over the warbling ambitions of the general public alongside Simon Cowell, Randy Jackson and Kara DioGuardi, so much so that she's nearly ruined the dour reputation she's cultivated in many a stony-faced photo op over the years.

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"When I got the phone call, I just couldn't believe it. I feel like I got the best job that there is. I'm still grinning from ear to ear," she bubbled to "AI" host Ryan Seacrest on his radio show Friday (via the London Daily Mail, which claims she's pocketing about $219,000 for the temp gig). "I'm going to try hard to pout and not shatter the illusion that I'm a moody cow, but I don't know if I can -- I'm just so happy."

The former Spice Girl added that she hopes to carry on Paula's role as the nicer one, because she knows "what it feels like to stand there and be judged and how it can feel when nerves really get the better of you," she explained. "I don't want to shatter anybody's dream. But at the same time, there's nothing wrong with a little bit of constructive criticism."

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Oh, and Victoria feels no guilt about sitting in for the absent Abdul, who decided not to return after reportedly failing to secure a deal that rivaled Simon's and Ryan's, because she believes everything comes down to karma.

"I'm a spiritual person, and I believe you get back what you put out there," says Posh. "I hope she does something that's bigger and better, and I hope she's going to be happy. She's great so she's going to be good at whatever she does."

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