diff --git a/phpBB/docs/CHANGELOG.html b/phpBB/docs/CHANGELOG.html
index 0897328949..e54c4fd9bb 100644
--- a/phpBB/docs/CHANGELOG.html
+++ b/phpBB/docs/CHANGELOG.html
@@ -100,6 +100,7 @@
 		<li>[Fix] Add terminating semicolons to JavaScript code. (Bug #58085 - Patch by nn-)</li>
 		<li>[Fix] Minor language fixes. (Bug #54855)</li>
 		<li>[Fix] Parsing urls in signatures properly uses config settings. (Bug #57105)</li>
+		<li>[Fix] Allow multibyte keys in request_var(). (Bug #51555)</li>
 		<li>[Feature] Support for Microsoft's Native SQL Server Driver for PHP (Bug #57055 - Patch by Chris Pucci at Microsoft)</li>
 	</ul>
 
diff --git a/phpBB/includes/functions.php b/phpBB/includes/functions.php
index 38f910974a..917433a970 100644
--- a/phpBB/includes/functions.php
+++ b/phpBB/includes/functions.php
@@ -114,7 +114,7 @@ function request_var($var_name, $default, $multibyte = false, $cookie = false)
 					{
 						$_v = null;
 					}
-					set_var($_k, $_k, $sub_key_type);
+					set_var($_k, $_k, $sub_key_type, $multibyte);
 					set_var($var[$k][$_k], $_v, $sub_type, $multibyte);
 				}
 			}