Okay, what I realize I didn't mention was that I was using JBoss 4.2.3, which, while it works, as I said, when the file is prefixed with "zzz", when the zzz was not there, it doesn't. I've been pouring through the logs and it seems that it is more of a classpath issue, which I still think is weird because it, theoretically, shouldn't work at all, no matter what I name the file.
I switched to JBoss 5.1 and it loads fine without error. I guess I'm running into some weird 1.5 vs 1.6 issue. I'll see if I can find any more information to post here in case it helps anyone else.