Now I believe they're *compatible* but i'm not sure how compatible. Some say apple supported 232 right out of the port for modems, but I'm not totally sure if I do whatever is needed to make it look like a 232 port if i'd get appletalk traffic, and then other sites say it's a differential interface, and you tie certain pins to ground, like TX- and RX- or something. I'm trying to find the link I found at work.

http://pinouts.ru/Converters/rs422_cable_pinout.shtml

Now we're talking.