Many Xperia Z users reported that the charging docking scratch the phone therefore need to do some surgery on the docking to avoid to hurt lovely Xperia Z anymore
The surgery tutorial: http://www.mobile01.com/topicdetail.php?f=569&t=3258351
Here I borrow McDonald's property to against the springs return
Video of plugin: http://flic.kr/p/eb7Xmr