No, I want to have the following functionality:

I post a message logged on as Zootee, but, for a specific post I may want to post as a non-registered username, but, the difference is that I would also want my registered username to appear as well. For instance:

Mr. Z (Registered User:Zootee)

should appear as the poster so that people are under no illusion that it is me doing hte posting but, I can adopt a pseudonym just for that post. The name used cannot already belong to a registered user.

Sorry, it's quite a complex request :)

Zootee