Mon serveur Minecraft bug

Depuis peu de temps je possède un serveur Minecraft sous Hamachi et quand je le démarre un message apparaît:

[INFO] Starting minecraft server version 1.6.4
[INFO] Loading properties
[INFO] Default game type: SURVIVAL
[INFO] Generating keypair
[INFO] Starting Minecraft server on *:25565
[WARNING] **** FAILED TO BIND TO PORT!
[WARNING] The exception was: java.net.BindException: Address already in use: JVM_Bind
[WARNING] Perhaps a server is already running on that port?

Merci d avance