I have seen a few problems in the character naming system. Could have to do with non-printing characters. First, I once did a shout and then someone else, with the same name and spelling as me, started doing shouts with all sorts of berating other people in it. However, there was one difference. There was a blank space in front of the [Name] block. Can't report this person... can't even tell who they were! Second, I had someone start saying in tells that I was their wife. So I went to ignore. No such player... so I used the recent tell menu to do ignore. no such player. Report... no such player. So no ability to ignore or report. I just stopped playing that character for now so the idiot stalker will have nothing to do. Both of these seem to have to do with people being able to play games with the chat system, their names, or something. It is very hard to replicate because these jerks only show up at odd times and i do not know exactly what ir how they are doing this. What i can assure you of is that it makes DCUO much less friendly to regular players. I mean, you have to turn of tell, shout, and say or you are going to be bothered by idiots. Then you have more trouble LFG, etc. If I could at least block the twits and report the stalker then it would be something. And if you can find that name cloning thing and shut it down I bet everyone other than the jerks would be happy. The only people to use it are trouble makers that go out of there way to harass people.
This happening in tells is odd. In any public chat, people can masquerade as others by including enough spaces in a block of text that the next line is bumped down. Knowing the next line is bumped down, the writer then inserts text to look like system generated code, like another user's name, for example. IE: [Jambo288274]: My cat's breath smells like cat food [Gogoxspeedwagonxx]: It's hot out today <user inserts a ton of spaces here, resulting in a line bump...> [Jambo288274]: I'M AN IDIOT <still Gogo's text> [Jambo288274]: I didn't say that. Now if you're getting tells and the message is in the appropriate color text for tells, then somebody is doing something shady on PC side.
Well yes it is "shady' but I have seen the tell trick done the same as they do in shouts (I have had it happen to me but it's a friend who only does it on me on purpose to pick on me because he secretly hates me and wants to kill me with a wet noodle). That being case you're probably right on the money with what the OP's problem really is
If it's happening with tells, then I imagine you're receiving tells from another player. If you expand the chat box window to full size (stretch it from the bottom left to as far to the top right as you can) it'll reformat the text spacing, and you'll see the obvious large numbers of spaces where it's still the same single ***** talking. If it's happening with a tell, then scroll up a bit to the last other person who sent the tell. Should be that person spoofing you.
That is probably how the shout faker did it. The direct tell was, well, a direct tell that could not be reported but could be replied to. proper collor and everythig, but I could not ignore them or report them. Very odd...
Try to take a screenshot and record the time. You have one support ticket you can have open at a time so gather all you can to try to report. The Devs should have logs and the timestamp you give should help, narrowing things like the report in game option, I hope