Found it:
http://www.tski.co.jp/baldio/patch/20030313.html
March 2003 Patch: Song of the Deep Seas now says: "The fury of the deep sea fills your arms" when sung (changed "see" to "sea").
Edit:
I actually think the entire proc is wrong, though.
Pre 2002, I think it should be this:
https://web.archive.org/web/20020228...tml?spell=1755
See history of changes to the proc:
https://lucy.allakhazam.com/spellhis...ve&setcookie=1
2002-12-12 11:18 Changed 'Cast on you' message from "You feel your pulse quicken." to "The fury of the deep see fills your arms."