import Blender
import bpy
from Blender import *

def main():

	bone_name = 'Bone'
	arm_object = bpy.data.objects["Armature"]

	arm = arm_object.getData()	
	arm.makeEditable()

	bone = arm.bones[bone_name]	
	edit_bone = Armature.Editbone(bone)
	edit_bone.deformDist = bone.deformDist
	edit_bone.head = bone.head
	edit_bone.headRadius = bone.headRadius
	edit_bone.matrix = bone.matrix
	edit_bone.options = bone.options + [Armature.NO_DEFORM]
	if bone.parent:
		edit_bone.parent = bone.parent
	edit_bone.roll = bone.roll
	edit_bone.tail = bone.tail
	edit_bone.tailRadius = bone.tailRadius
	edit_bone.weight = bone.weight
	
	del arm.bones[bone_name]
	arm.bones[bone_name] = edit_bone

	arm.update()
	Window.RedrawAll()

main()