No i dont think there are any tools available within the forum script which allows the admins nor the super mods to verify the proxy addresses.
They take help of external sources to learn such a things.
Foe example if a person's access ips change everytime it is evident that either he is using a proxy or any suspicious behavior would attract the attention of the admin so they manually check the ips and learn that its a proxy

But i am not sure about such tools available within the forum scripts