Chris Rock, who listed several attendees of Obama's birthday bash. UPI/Robin Platzer | License Photo
The replica Oval Office at Madame Tussauds with figures of President Barack Obama and Oprah Winfrey is seen decked out with "presents", balloons and streamers on President Obama's 50th birthday in Washington, DC, on August 4, 2011. UPI/Roger L. Wollenberg | License Photo
WASHINGTON, Aug. 5 (UPI) -- Comedian Chris Rock said via Twitter Herbie Hancock and Stevie Wonder helped President Barack Obama celebrate his 50th birthday at the White House.