Apologies - I didn't read as far back as 9 years ago to discover that the issue had been previously reported.
Yes - I accept that the IRC RFCs may specify usernames up to 9 characters, however:
1. mIRC itself allows userids of up to 10 characters on the IDENT options page. $address(nick,5) works on these, but $address(nick,6) still truncates the first character.
2. As stated in that link, the RFC states "While the maximum length is limited to nine characters, clients SHOULD accept longer strings as they may become used in future evolutions of the protocol." and mIRC doesn't follow this.
3. I found this because I use the $address(nick,5) to add addresses to the DCC trust list and DCC sends were failing - so mIRC is inconsistent in its handling of userids longer than 10 characters, using the full userid when comparing with the trust list but only the first 10 characters when providing it in $address(nick,5).
4. Perhaps, as mIRC already does in many other cases, mIRC needs to have adjustments to work with real-life servers which are outside the formal spec in minor ways like this.
