You may be on a server that has been listed as spam by AOL. When that happens, the entire server is blocked, not just one account.
That's going to be happening more frequently. Reporting Spam to AOL is very, very easy. Just click on the e-mail in the list, hit
spam button at the bottom and it swooshes off and reports itself as spam.
If you are being blocked, your host will have to contact AOL and assure them that the spammer has been eliminated. Then, after a couple of days, you may be able to get mail through.
You can find out more about how AOL handles e-mail here:
http://postmaster.info.aol.com/