I rebooted after I uninstalled both older rotate and icewm, but not after installing new versions.
I just now rebooted (again), and tried rotating the physical screen. Nothing changes. I tried this with ROX (as a desktop), enabled and not enabled.
I have never seen my screen rotate to PDA mode in any icewm versions that I have tried, unless I use the rotate icon.
Also, when using the rotate icon, and switching back to laptop mode, the taskbar disappears, (icewm only). The taskbar is still there, but it is below the bottom of the screen, because the menu button works, but it is shifted down a space or two.
I have no problems in openbox, rotating the screen works the same as in Sharp/Cacko.
I haven't been too concerned about this because I never use this Zaurus in PDA mode. I just thought I would mention it.