What are the MathOverflow guidelines regarding using pseudonyms in place of one's real identities? In particular are anonymous/pseudonym users treated differently from users who use their real identities in anyway? In particular, do moderators apply rules more strictly towards pseudonym users?

Also are there any rules regarding using multiple accounts?

Have there been any discussion about these issues before on meta or tea? (I remember I have seen some comments regarding this on meta but do not recall where exactly.)