scan subdirectory of mailbox with PHP

[brian]

I'm fiddling with the woefully under-documented PHP IMAP functions and 
cannot figure out how to do this. I can connect just fine to INBOX, list 
the headers, etc. but my target mails are a couple of directories 
further down. I'd like to somehow do the equivalent of chdir once i've 
made a connection.

Does anyone know how i can achieve this?
brian
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