I want to develop a third person game using ogre and ogrebullet.but I don't know how to use btKincetCharacterController and what is the relationship between CharacterController and ghostObject?Could any body give me a sample?and does ghostObject means that If I want to move the object in ogre I need to get the position of ghostObject and set the node of object in ogre of the position?

I think you'll have a better chance of getting an answer on the ogre addons forum. This one is for OgreBullet specifically: http://www.ogre3d.org/addonforums/viewforum.php?f=12&sid=000a4431878c8f532b86958169f73689