We're currently using 4.6.8 with Drupal 7, and we're currently finding that if you re-use an old mailing, but then change the From address, the Reply-to field remains according to the original mailing and is not changed. The result is that the Reply-to field is set incorrectly, confusing recipients as well as the owner of the incorrect Reply-to email address. Is anyone else having this problem?
The issue was that the replyto_email field wasn't being updated by angular to pass it back to the database. I believe this was fixed in https://issues.civicrm.org/jira/browse/CRM-17650