Its unlikely musicians used equal temperament 3,400 years ago. This is a guess, and that fact is reinforced by the other "interpretations" referenced in the article. It's fun to imagine, but this not a "Rosetta Stone for music" moment.
I believe the article may be talking about the Hurrian Songs:<p><a href="http://en.wikipedia.org/wiki/Hurrian_songs" rel="nofollow">http://en.wikipedia.org/wiki/Hurrian_songs</a><p>This is an interesting point from the wiki entry:<p><i>Astonishingly, there are no known terms corresponding to a single note, or to intervals of a seventh or seventh</i><p>I'd like to hear some other views on how these tablets have been interpreted.<p>(as an aside: I'm under the impression that it's wrong to describe these as <i>Sumarian</i>, as they were a quite distinct and separate group)