Pen as an input Device

Hi All,
When i go in the Device editor, it shows me 2 existing Devices:
Pen & Puck under Wintab
I would like to use my Pen as a Mocap Device
I can make attachement of what attribut i want
on say Pen:X
but it won't work when i rehearse or preview
I'm new to Device Editor, i have read the online help
and i'm sure i forget something.
did that sound something for you ?
Jean-marc