postfix upgrade does not add 'retry' service

Binary package hint: postfix

Doing an upgrade from feisty to gusty, postfix gets upgraded from the 2.3.x series to the 2.4.x series.

As per the release notes here:
ftp://ftp.reverse.net/pub/postfix/official/postfix-2.4.6.RELEASE_NOTES

There is a "Major changes - critical" feature added to the 2.4.0 release as follows:
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[Incompat 20061209] The upgrade procedure adds a new "retry" service
to the master.cf file. If you make the mistake of copying old
Postfix configuration files over the new files, the queue manager
may log warnings with:

    warning: connect to transport retry: Connection refused

To fix your master.cf file, use "postfix upgrade-configuration"
followed by "postfix reload".
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I discovered after my gutsy upgrade that this feature was *not* added to my master.cf. I don't believe the install procedure gave any warning of this, so it was purely chance that I noticed it in the release notes. Running 'postfix upgrade-configuration' manually did in fact modify my master.cf without causing any problems for my existing config. The upgrade procedure should probably call this function at post-install, or at very minimum, warn the user to run it.