[Dovecot] Opinions on preferred namespace?

[Ed W]

Hi

Any opinions on a preferred namespace setting for use with Dovecot?

Deciding factors seem to be client support, not being too unusual, 
accidental ease of setup, wider character range support (eg dots in 
folder names?), issues when scripting imap commands?

For example Outlook Express (common with our userbase) seems to assume 
no folderprefix when using our current Courier server and from memory I 
think this causes some subtle issue with Sent Items and Drafts folders 
until you tell it to use an INBOX. folder prefix?  (can't recall the 
exact details right now)

I notice also that Thunderbird will show all folders under "Inbox" if I 
have an INBOX. prefix, but shows them all in a list if there is not 
one.  Actually I find the former quite a useful feature because I have a 
number of test accounts where I only want to click into the INBOX, do I 
can keep the list of folders closed up

Any other programs exhibit any (possibly beneficial) side effects from 
different prefix choices?  Anyone got any preferences either way?  Any 
pros/cons in using a dot as folder separator rather than a slash?

I can see some logic in using an INBOX folder prefix and a slash as the 
folder separator because this would then mimic the on-disk layout.. (Is 
this what cyrus does?)

I mainly care about best support for Outlook Express / Windows Mail and 
Thunderbird - any opinions on most compatible settings?

Cheers

Ed W