Background:
Filemaker Pro 10+ have gained functionality to send emails using SendMail via SMTP. There are expensive (relative to total FileMaker licensing cost) plugins that can do SMTP on FMP earlier than 10, but that investment is not an option.
I have set up a network that I'm managing (I'm not mainly a developer) to use Thunderbird as their email client since I have seen repeated mail corruption and loss with Apple Mail.app (in fact, during migration we found that Mail had already mangled some of their folders), but Thunderbird as default client does not seem to work with FileMaker in sending email. Which is strange, because it seems to work on Windows.
Now my questions for FileMaker developers:
Is there a way to make FMP 9 either use SMTP (for free) or to actually send emails (not just open one and fill the fields like with the mailto: protocol - this is needed for mass-mailings like customer newsletters) using Thunderbird as the default client?
Failing that, is there a way to set a mail client to be the default only for FileMaker? I guess even Mail would be acceptable if it's only used for sending from Filemaker, I could just let it write its sent mails to a specific IMAP folder...