use special characters in usernames

Hi there,

I’m from Hungary, and because I’m going to have to connect to a separate database (non WP based of course [I know it shouldn’t be done, but I’m not the boss in the office]), where the usernames can have special characters like ‘?’, ‘á’ or ‘é’.

The problem is, the login will be handled through a CAS server on that site, so even if I put the usernames into that database sanitized (as WP does), they won’t be able to login from the ‘central’ login server if they try to use special characters.

Here’s what I tried so far:
I found this million-year old topic:
https://www.ads-software.com/support/topic/special-characters-in-usernames/
and I followed the instructions there, but no change happened, usernames are still sanitized.

I also tried to replace some characters in that sanitizing character table or whatever (ie the remove_accents function in formatting.php) so that they change the character ‘á’ to ‘á’, but the result was the same.

I tried to mess around with some other things, but basically the only difference I could make is that during a login WP wasn’t able to find the username in some cases, but said username can't be empty , or the user was created with the special characters replaced by nothing (so instead of béla it was just bla).

At this point I’m just lost. Is there any way to tell WP to store usernames with special characters? It doesn’t matter how messy it is, if it’ll work, I’m gonna be happy.

Oh btw, everything in the database is set to utf-8, so that can’t be the issue.

If anyone has any ideas, it will be appreciated.

Regards,
Kacsa