I think I've jumped the gun a little, I'm afraid.
I've been digging around for a cite for this to make sure I was right. I haven't found exactly what I'm looking for. I think I misinterpreted what I heard.
I was partly right though. I found a few things:
It seems the author has an axe to grind against Judaism and Christianity, but it'll have to do for now.
from
WOMEN IN ISLAM VERSUS WOMEN IN THE JUDAEO-CHRISTIAN TRADITION:
THE MYTH & THE REALITY
I should point out that when he says Judaism allows it, he is making a pretty big generalization about the religion and their interpretation. However, around the time of Jesus I do believe that this kind of thing was in Jewish law.
It looks like I was also wrong about that particular custom being behind this. A lot of the things that Islam is criticized for are cultural customs from that time that Christianity and Judaism participated in, but not this one.
However, what it apparently does say in the Koran nonetheless should be looked at.
From
Legal Affairs
So even though I was wrong about the connection to Islam, the way people say their divorce works is still wrong. I'll try to ask some people who might know, because I don't really trust these cites too much, but I think what I've found out is at least close to the truth.
Sorry about that. It just goes to show: always ask for a cite