We are on the same clue....
Like Toaster (really good) but need to use the "Send as Mail to..." feature. Is not only a question of not to use this (we can instruct users to save a document and then send it as an attachment in Zimbra web client...). The question is that some Windows apps use this to automatically send mails (i.e.: an accounting app that monthly sends mail to each customer...).
I been reading thes posts and saw something about using Thunderbird (or another app) with IMAP. Anyone tested it?
If we can't find a good solution we cannot migrate to Zimbra (and, at
last, say goodbye to Exchange/Outlook)
PD. I voted for bug 12845