error(8) on macOS
The text bb729ca8703b, as Mac OS X 10.6.8, Mac OS X 10.6.7, Mac OS X 10.6.6, Mac OS X 10.6.5, Mac OS X 10.6.4, Mac OS X 10.6.3, Mac OS X 10.6.2, Mac OS X 10.6.1, Mac OS X 10.6 shipped it.
Postfix error/retry mail delivery agent
The text bb729ca8703b, as Mac OS X 10.6.8, Mac OS X 10.6.7, Mac OS X 10.6.6, Mac OS X 10.6.5, Mac OS X 10.6.4, Mac OS X 10.6.3, Mac OS X 10.6.2, Mac OS X 10.6.1, Mac OS X 10.6 shipped it.
Postfix error/retry mail delivery agent