Drew -- If you allow (or maybe even force) html messages and do not click the "remove other reply options" box in settings there should be a "Reply to Sender" link in the message footer.
Hi Bruce.
No, there is no Reply To Sender footer link in received plaintext message posts (only View/Reply Online; Mute This Topic; Group Owner; Unsubscribe.)
That is known, hence Bruce's suggestion. All of your messages would then contain that footer.
