Maybe it's his confirmation name? I'm a Sting nerd and I've never seen it anywhere else either.
 
Katie
Santiago, Chile 
From: ross@rossviner.com
To: Police@mailman.xmission.com
Date: Sat, 28 Feb 2009 23:16:49 -0800
Subject: [Police] Gordon Matthew "Thomas" Sumner

WTF?  Is one of his names really "Thomas"?
http://en.wikipedia.org/wiki/Sting_(musician)
 
and I thought I was a fan.  not worthy.
 
I'll return my card.

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