How 'bout Sentry 2020 for Pocket PC? I've been looking at this one - have not tried it yet, but its feature list is impressive and it IS WM5 compatible. List of features:
Key Benefits
- Supports all Windows CE storage media: compact flash, MMC/SD, etc.
- Strong encryption: Twofish-256, CAST-128
- Encryption key can be stored separetely on different media
- Multiple volumes
- Volume inactivity time-out
- Command line interface
- Install and Uninstall options
- Compatible with Sentry 2020 for Windows XP/2000/NT
Check it out at:
Sentry 2020