By automatically obtaining the entirety of a received message to be included, an outgoing message that includes the received message can be processed in a manner that securely and accurately represents the intended outgoing message. Alternatively, a server can assemble a composite message from a new message and an original message and, in cooperation with a wireless messaging device, sign the composite message. In both the above contexts, handling message receipts when message processing ahead of message transmission involved more than one component may be facilitated by storing appropriate expected receipt content during the message processing, either on the device or the server. Validation of the receipt can then be accomplished through use of the stored expected receipt content in a manner that retains the benefits of message processing ahead of message transmission that involves more than one component.