The most current version of qmail is 1.03.
It was finished, and released, on June 15, 1998.
No work has been done on the source code since.
In compliance with the license under which qmail was released, all distributions must be of either this source code, or of object code created directly from the source code.
Any changes, additions, extras, etc., introduced between then and now have been, and are, introduced by making patches to the source code and then recompiling.
I know a lot of people who believe this model is the best way to distribute software, but frankly, I prefer to use software currently under development by it's author(s) with input from others.
And that's why, as do the DA staff, I prefer exim.
Jeff