go ahead and remove the sim card. place it into an old flip phone. once the phone powers up go into the phonebook settings and look for my number or my info or worded something like that. it should say msid and it should be empty. go ahead and edit it and insert your own number and name. once your done applying that click on it again to double check. now it should have your info stored on the sim card.
once you get that done put your sim back into the optimus. once that powers up if you haven't edited your profile then do so. go to contacts, menu, more, my profile. edit your info and you should have your picture showing on your threads.