It's most likely AOL's fault. vbulletin uses sessions to track what you are doing on the site and it stores your ip and browser info. AOL's ips change dynamically, so the sessions do not work correctly. But then, some people who use AOL are able to vote, so I'm not really sure how they have it set up. There is a way to pass the session info via the url, but I haven't figured that out yet.

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-Kalvin