Hi all !

Zimbra ZCS 6.0.5 on Centos5 here.
We have a problem when saving large messages to our Drafts IMAP folder.

We use Thunderbird 3 as our mail client, but I think it is not to blame : I have a Google Apps account and a Zimbra account setup on my thunderbird profile (same settings), and Gmail works whereas Zimbra gives an error.

I am not sure what the size limit is, but joining a 1MB attachment (xls file, just for testing purpose) does not work.
On the server, the mail size limit is set to 10MB.

When saving the message, the progress bar is immediately at 100%, even though Thunderbird is still sending the message (I can see this in network monitor). When sending is complete, I get an error (something like "there was an error while copying your message, would you like to try again").
If I check the Drafts folder, the message is there, intact, no problem.

I checked Thunderbird's IMAP log, but it is HUGE (event if I just enable it before saving the message), and I don't know what to look after. There is not obvious error message in there.

Any advice on this would be greatly appreciated !