diff --git a/phpBB/docs/CHANGELOG.html b/phpBB/docs/CHANGELOG.html
index ef50e08453..f5baf664e7 100644
--- a/phpBB/docs/CHANGELOG.html
+++ b/phpBB/docs/CHANGELOG.html
@@ -123,6 +123,7 @@
 		<li>[Fix] Deleting private message attachments could delete post attachments. (Bug #42815)</li>
 		<li>[Fix] Do not suppress PHP notices/errors in language packs if DEBUG_EXTRA mode enabled. (Bug #41485)</li>
 		<li>[Fix] Flash files do not display anymore after update to flash player 10 (Bug #41315)</li>
+		<li>[Fix] Use FQDN for SMTP EHLO/HELO command. (Bug #41025)</li>
 		<li>[Change] Allow download of conflicting file for later reference in automatic updater</li>
 		<li>[Change] Default difference view is now 'inline' instead of 'side by side'</li>
 		<li>[Change] Added new option for merging differences to conflicting files in automatic updater</li>
diff --git a/phpBB/includes/functions_messenger.php b/phpBB/includes/functions_messenger.php
index 14465ef13c..6c8f8aa32d 100644
--- a/phpBB/includes/functions_messenger.php
+++ b/phpBB/includes/functions_messenger.php
@@ -1073,7 +1073,7 @@ class smtp_class
 		global $user;
 
 		$err_msg = '';
-		$local_host = (function_exists('php_uname')) ? php_uname('n') : $user->host;
+		$local_host = (function_exists('php_uname')) ? gethostbyaddr(gethostbyname(php_uname('n'))) : $user->host;
 
 		// If we are authenticating through pop-before-smtp, we
 		// have to login ones before we get authenticated
diff --git a/phpBB/includes/session.php b/phpBB/includes/session.php
index 49f97f6050..b01d0b2281 100644
--- a/phpBB/includes/session.php
+++ b/phpBB/includes/session.php
@@ -182,7 +182,7 @@ class session
 			else
 			{
 				// Set to OS hostname or localhost
-				$host = (function_exists('php_uname')) ? php_uname('n') : 'localhost';
+				$host = (function_exists('php_uname')) ? gethostbyaddr(gethostbyname(php_uname('n'))) : 'localhost';
 			}
 		}