I guess they found a legit-sounding way of describing it. Rather than work out any kinks with a theoretical MMS functionality, they bring in the whole fear or unsolicited porn. Rather than just working out a way to prevent MMS spamming they blocked MMS in general on PPCs. I'd be interested in seeing if there were ever any such complaints or if it's just a hole that could be exploited with Windows (mobile or otherwise) and the MMS protocol. I'm sure any porn spammer could just as easily alter their script to send an email to
123-456-7890@pm.sprint.com instead of just sending an mms to 123-456-7890.