diff --git a/CHANGELOG b/CHANGELOG
index 103bc6770..399f1449f 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -17,6 +17,7 @@ CHANGELOG Roundcube Webmail
 - Elastic: Improved UX of search dialogs (#6416)
 - Elastic: Fix unwanted thread expanding when selecting a collapsed thread in non-mobile mode (#6445)
 - Log errors caused by low pcre.backtrack_limit when sending a mail message (#6433)
+- Fix so unicode in local part of the email address is also supported in recipient inputs (#6490)
 - Fix bug where autocomplete list could be displayed out of screen (#6469)
 - Fix style/navigation on error page depending on authentication state (#6362)
 - Fix so invalid smtp_helo_host is never used, fallback to localhost (#6408)
diff --git a/program/js/common.js b/program/js/common.js
index 406ca23a4..1422042ad 100644
--- a/program/js/common.js
+++ b/program/js/common.js
@@ -402,7 +402,7 @@ triggerEvent: function(evt, e)
 // check if input is a valid email address
 // By Cal Henderson <cal@iamcal.com>
 // http://code.iamcal.com/php/rfc822/
-function rcube_check_email(input, inline, count)
+function rcube_check_email(input, inline, count, strict)
 {
   if (!input)
     return count ? 0 : false;
@@ -438,7 +438,7 @@ function rcube_check_email(input, inline, count)
         '\\u05d1\\u05f2\\u05b7\\u05e9\\u05e4\\u05bc\\u05d9\\u05dc\\x2e\\u05d8\\u05e2\\u05e1\\u05d8'
       ],
       icann_addr = 'mailtest\\x40('+icann_domains.join('|')+')',
-      word = '('+atom+'|'+quoted_string+')',
+      word = strict ? '('+atom+'|'+quoted_string+')' : '[^\\u0000-\\u0020\\u002e\\u00a0\\u0040\\u007f\\u2028\\u2029]+',
       delim = '[,;\\s\\n]',
       local_part = word+'(\\x2e'+word+')*',
       addr_spec = '(('+local_part+'\\x40'+domain+')|('+icann_addr+'))',