Sam Varshavchik wrote:

All courier-imap folders except of inbox are incompatible with almost all other maildir clients (especially shared folders but that's another story). So I see no reason on having a compatibility with other mail readers for any folders _except of inbox_. Yes, it isn't a good idea to have different format for different folders. But anyway, the "proposed maildir format" have some significant advantages so it can just replace "plain maildir" IMHO. Moreover, it may be ok to rename files in cur/ directory also (not only when moving from new/ to cur/) -- when courier used together with some other program to access maildir. Just see a message name and rename to next msgno (with possible preserved flags) if a name isn't numeric. This will break some e.g. pop3 clients that will see some messages twice (if pop3 daemon uses message name as an uidl), but even if both are true -- maildir accessed by courier _and_ some other software and if that other software uses filename as an uidl or something like this. Courier already comes with pop daemon -- for that, there is no conflicts since it uses the same code to access maildir. People may prefer to use other pop daemons (e.g. qmail-pop3d), but those can easily be patched. Also, as a last resort, if maildir isn't exported via nfs, one can modify LDA to use last message number as filename when initially creating file in tmp/&new/)...

Wooh... That to say is that in _most_ (not in all) cases this scheme will work out-of-the-box, and in some rest it is easy enouth to avoid. Sounds like a good think to try... :)

As I said, NS loads folder summary only (numbers and flags). But IMAP protocol is "fat" here -- about 30..50 bytes for each message "* 137 FETCH (UID 555 FLAGS (\Seen))", so if there are many messages, this will require big network traffic (probably 10mbit ethernet is yesterday... ;)