You can install OneNote Mobile on a Windows Mobile 2003 device manually, I've written a
HOWTO (but it's in german)
In Short:
1. get cabwiz.exe, cabwiz.ddf, makecab.exe from Windows Mobile SDK (these files are included in serval versions of the SDK)
2. get
http://www.tomhost.de/gate/downloads...te_on_2003.zip
3. copy/unpack all into a new folder
4. copy OneNoteMobile.cab from your Office Installation Path/Office12/1031 to this folder
5. run convert.bat, confirm to write some stuff (see service.reg) into your reg
6. copy OneNoteMobile.cab to your PDA und run it
Works well for me...