Whoops--my bad :)
You are right...I should have mentioned that the commentaries were of later Greek translations. The original Hebrew word was yom, which, when paired with an ordinal (number), consistently meant a 24-hour day.
I figured it was a "typo." I would have ignored it except that those who do not believe in a literal 6 day creation use every opportunity they can to prove us to be uneducated. Whatever we say, we should research it thoroughly.
Shalom.