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Madonna, Miley and MTV are coming together Wednesday night.  The veteran pop star will reportedly share the stage with Miley Cyrus on Cyrus' MTV "Unplugged" special. 

Madonna, who was a last-minute add to Sunday night's Grammy Awards, has been outed as one of the special's surprise guests. 

Sources tell E! News the "Material Girl" was spotted rehearsing with Miley on a Hollywood soundstage Monday. 

Miley's "Unplugged" is set to air Wednesday night, starting at 9:00 pm Eastern.

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