Gunter Thielen, the new head of Bertelsmann, will stop by the Gruner + Jahr USA subsidiary today -- as war erupts between the magazine company's CEO Daniel Brewster and Rosie O'Donnell.

Rosie, the editorial director of Rosie magazine, wants to push out new editor Susan Toepfer, who arrived from People just a month ago. 

Unlike Oprah Winfrey, who has the final say on editorial in Hearst Corp.'s O, the Oprah Magazine, Rosie's contract apparently left a lot of the personal decision-making to Brewster and the magazine pros. 

Rosie is now pounding the table and saying she wants to run the show and kick out Toepfer, Brewster's hand-picked editor. 

"It's about control," said a source close to Rosie. "She wants to control her magazine." 

The dispute apparently isn't about buying the magazine, which was born from the 125-year-old McCall's. A purchase would cost $20 million or more. 

"I don't think she wants to own the magazine," said the source. 

But she does want her stamp on it. O'Donnell was infuriated by the palace coup that bounced Cathy Cavender as editor and replaced her with Toepfer and then, a week later, resulted in the firing of art director Doug Turshen. 

Toepfer has brought in a freelance art director, Holland Utley, to help with the next few issues. 

And as Women's Wear Daily reported yesterday, O'Donnell is serious enough about the issues to retain former high-powered U.S. Attorney Mary Jo White as her lawyer. 

"She has hired Mary Jo White," confirmed O'Donnell spokeswoman Cindi Berger at PMK. 

Regarding the magazine's direction, Berger said, "She does not want to turn it into an entertainment magazine. She wants smart, provocative pieces that will appeal to women and empower women." 

O'Donnell has been scarce at the magazine since her Alexander Haig-like "I'm in control" speech to staffers two weeks ago. She has shown up only once -- but is expected to be back in force next week. 

She will not be at the meeting today when Thielen talks with senior management -- which, according to insiders, is a move to bolster and assure Brewster. But that was before the Rosie brouhaha erupted. A G+J spokeswoman declined to comment.

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