https://www.icyphoenix.com/viewtopic.php?f=35&t=7009&p=48189#p48189
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TheSteffen
Mon 08 Mar, 2010 17:33

Re: Nickname With Russian Letters
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Have you done this?

OPEN [b]includes/functions_validate.php[/b]
FIND
[codeblock]if (!preg_match("/^[a-z0-9&\-_ ]+$/i", $username))[/codeblock]
REPLACE WITH
[codeblock]if (!preg_match("/^[a-z0-9&\-_ &#1072;-&#1103;]+$/i", $username))[/codeblock]

Or maybe this
[codeblock]if (!preg_match("/^[a-z0-9&\-_ &#1072;-&#1103;]+$/i", $username))[/codeblock]

For me it is working... but I only used some spezial letter like ÄÖÜäöüß


