Hi yqin!
I downloaded your VI and tested it on a PocketPC with the same results. It looks to be a bug of some kind in the Scan String for Tokens.vi like you mentioned. I'm going to alert R&D of this issue. However, as a workaround, you could make use of the Match Pattern.vi or Scan String.vi. I realize this may take a little bit of extra coding, but it might help you to get through this hold-up for the time being.
Hope this helps!
Travis H.
National Instruments
Travis H.
LabVIEW R&D
National Instruments