I had a similar situation in terms of greek with a fellow student at my Karate school. His license plates on the two family cars are AEKDB13 and 13AEKDB. He was founder #13 at the Kappa Sigma chapter at Towson State University (Maryland). AEKDB apparently are the initial letters of the secret motto of Kappa Sigma. The fact that those letters represent Kamma Sigma isn't secret though, the greek equivalents (Alpha Epsilon Kappa Delta Beta) are on the scroll at the bottom of their coat of arms.
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http://en.wikipedia.org/wiki/Kappa_Sigma)