When adding "Editable Email Notification" as a post-build action, I am seeing that $DEFAULT_RECIPIENTS is always set in the Project Reply-To List field by default, instead of $DEFAULT_REPLYTO. All the other fields have their $DEFAULT_xxx variables matching their corresponding field, but it looks like there may have been a copy/paste oversight and the wrong default variable is being used for the Reply-To field.

See screenshot: http://i.imgur.com/Ckq1UHl.png

I've tested a fix for this and will submit the diff in a Pull Request on the GitHub project for email-ext.