Comment 3 for bug 290443

Given that line 24 of main.cf has "failed minimal_backoff_time = 1000s", I'm going to assert that it's not the default config, since nothing in the default install actually even tries to set minimal_backoff_time, and certainly not with "failed<space>" in front of it.

Invalid preexisting configuration, I expect that postfix wasn't even starting before the upgrade.