Says server is Offline in server listings when it is not

On planet minecraft it says my server is offline in the server lists, when it is online and you can join. It is not cracked or anything. It is port forwarded and uses bukkit. This issue is causing players to skip past and not click on it, so no one is ever on my server that I spent 3 years on. If you can fix it, or tell me how to fix it that would be great! Thanks, flash110.