You may know about it but I just found this - it explains about the WM5 GPS splitter that I mentioned in reply #25 in this thread.
http://blogs.msdn.com/windowsmobile/...07/620387.aspx
Assuming that it exists in WM6 you could invoke this in built-in splitter to pass the GPS (COM4 I believe) to an unused COM, say COM6 and try with the serial2 libary. If this doesn't work then try adding the JAL Post Splitter inputting from COM6 and outputting to COM7. Clutching at at straws I know but maybe worth a try.