mailto: subject= and body= support in email clients

Question

Does anyone know if when sending a html newsletter what kind of support the major email clients have for the subject= and body= parts of the mailto tag?

Answer 1

I imagine they've got quite good support for it. BUT!! But mailto will be used to send and email FROM the client TO me@somewhere.com . Thats definitely not you sending out a newsletter.

You'll have to send emails from the server, potentially in a background process.

EDIT: Slight rethink. Are you talking about you using an admin section with a link with multiple TO addresses that will then open an email client to send out your newsletter? In which case, even though the major browsers probably do have decent support, you shouldn't rely on it out in the wild, since its not in the standard (I think), so they are not required to support it.

EDIT AGAIN:

rfc 2368 info in support of my previous edit