One of these options enables the user to change the reply address of the text.

FORBES: French Hacker Claims That Every Single iPhone Ever Made Vulnerable To SMS Spoofing Bug

French jailbreak developer and security researcher pod2g finds that every iPhone firmware revision, even iOS 6 beta 4, is susceptible to a flaw that theoretically lets a ne'er-do-well spoof the reply address of outbound SMS messages.

ENGADGET: iPhone reportedly vulnerable to text message spoofing flaw

As Apple is using the reply-to address of a message's User Data Header to identify the origin rather than the raw source, receiving iPhone owners risk being fooled by a phishing attack (or just a dishonest acquaintance) that poses as a contact or a company.

ENGADGET: iPhone reportedly vulnerable to text message spoofing flaw