[Users] How to move the preferences folder to another dir?

[Ben Stover]

As far as I can see Claws-Mail (under Windows 7) uses the following directory by default as its preferences fodler:

C:\Users\<username>\AppData\Roaming\Claws-mail\

How can I tell Claws-Mail to use another directory e.g.

D:\mail\claws\myprefs\

Can I simply move the old pref files+subfolders to the new location and start Claws-Mail with a cmdline parameter like

claws-mail.exe -prefdir="D:\mail\claws\myprefs\"

Maybe I can move the pref dir to a subfolder of the installation directory and Claws-Mail will auto-detect it without having to pass a 
parameter...?

Ben