I use Qpopper in MBOX format with outlook 2000 ok, I haven't got around to using SSL yet.. In my enviornment (Gentoo Linux) I defined a global USE variable that directs mail applications to compile with "mbox" capability. When I used RedHat 7-9 it was just automatically in mbox format.
mbox and mbx are two different formats. mbox is the traditional Unix text format. mbx is a format used by the c-client library (part of the UW-IMAP package). Like mbox, a folder is a single file. But it includes a binary header that maintains folder metadata, making the file more efficient to search. You can use it with sendmail/procmail by using the dmail delivery program. Unfortunately, qpopper lacks any code to access this format of file. Ideally a patch would use the c-client library to accomplish this access, guaranteeing compatible locking semantics with dmail and other UW-IMAP utilities.
