That match ended in a simultaneous Pin on Angle/Tapout by Taker (well, it did on a re-shoot anyway), which I BELIEVE is the only known occurrence of Undertaker tapping out.
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Thank you, Eddie Guerrero.
http://www.wwe.com/f/styles/photo_large/public/photo/image/2012/04/33_Moscow_04112012jg_02128.jpg