Http://wishidknownthat.blogspot.com/2009/04/fixing-wacom-bamboo-pen.html

^ I believe this is exactly what you need to know. :3

Http://abiamy.com/abiyasablogs/2008/04/06/fixing-a-broken-wacom-pen/
Do this I swapped it and fixed everything it was a little complicated but worked

Lf only one end of the pen is not working and you dont use the other end, you can unsolder the copper coils eon-both ends and swap them over. Tip for opening: lift up the small blue bit nearest to the top, and then pull.

Same here I got an RMA refferal for a free pen from Wacom with or without registation!!!!