[sylpheed:33709] Save sent messages to outbox - Where's 'outbox'?

[Michael A. Puls II]

Sylpheed 3.0.0 - WinXP - IMAP

'Configuration -> Common Preferences -> Send -> General -> "Save sent  
messages to outbox"'.

I'm not sure what that means. I don't see 'Outbox' anywhere. I see  
'Queue'. Does it mean to only queue messages? Or, does it mean to not  
append messages to the specified sent mailbox even if one is specified? I  
see something about this mentioned at  
<http://sylpheed.sraoss.jp/doc/faq/en/sylpheed-faq-3.html>, but it's still  
not clear as I don't see "outbox" anywhere.

Does it mean "Queue messages (do not send immediately)"?

-- 
Michael