Comment 81 for bug 308181

Taken from my comment to bug 389275, this proposal has the following disadvantages:

- Uses DNSSEC, which is not widely deployed and has well-known deployment and operational issues (like DNS root and most TLDs not being signed).

- Requires an effort of DNS coordination when a single e-mail provider wants to
deliver automation for accounts under multiple domains, as opposed to providing
auto-config for a single (own) domain.

- Forces the user to enter his own data, and hence does not cover the important
case where you provide a configuration file with ALL the account's
configuration (including e-mail address, IMAP/POP user id, default folder
names, and perhaps even password), to prevent users from making mistakes.