I had configured email limit to 60MB but even a 19MB attachment would not come trough and I was told by antispam admin "to increase pop3 timeout". I seriously do not understand what it had to do with SMTP in terms of attachment sending to zimbra.

$ postconf | grep message_size_limit
message_size_limit = 62914560
BTW, I had reloaded postfix after message_size_limit configuration.

Any idea/tips would be appreciated