imap_listsubscribed() has been changed (or atleast I think has been) in php4b4 or the current CVS version.
The new function call is imap_lsub() it works the same as imap_listsubscribed()...
(PHP 4, PHP 5)
imap_listsubscribed — Alias of imap_lsub()
This function is an alias of: imap_lsub().
add a note User Contributed Notes imap_listsubscribed - [1 notes]