Me and my group are wondering: If someone who can teleport is being held in chains, can he teleport away? Do the chains around him teleport with him, or do they fall to the ground and the character is free?
From the Rules Compendium: pg 214
Immobilized or Restrained: Being immobilized or restrained doesn't prevent a target from teleporting. If a target teleports away from a physical restraint, a monster's grasp, or some other immobilizing effect that is located in a specific space, the target is no longer immobilized or restrained. Otherwise, the target teleports but is still immobilized or restrained when it reaches the destination space.
So, if they are chained to something, they teleport free. If they are just tied up in chains, the chains teleport with them.