diff --git a/hwe/j_msg_submit.php b/hwe/j_msg_submit.php
index 51bd87b9..dbaba7e0 100644
--- a/hwe/j_msg_submit.php
+++ b/hwe/j_msg_submit.php
@@ -161,7 +161,7 @@ if($mailbox > 0) {
     }
 
     $destPermission = checkSecretPermission($destUser, false);
-    if($permission == 4 && $destPermission == 4){
+    if($permission == 4 && $destPermission == 4 && $destUser['nation'] != $me['nation']){
         Json::die([
             'result' => false,
             'reason' => '외교권자끼리는 메시지를 보낼 수 없습니다.',
diff --git a/hwe/js/msg.js b/hwe/js/msg.js
index b812cc49..b70eaf93 100644
--- a/hwe/js/msg.js
+++ b/hwe/js/msg.js
@@ -385,7 +385,7 @@ function refreshMailboxList(obj){
 
             var $item = $('<option value="{0}">{1}</option>'.format(generalID, textName));
 
-            if(permissionLevel == 4 && isAmbassador){
+            if(permissionLevel == 4 && isAmbassador && myNation.mailbox != nation.mailbox){
                 $item.prop('disabled', true);
             }
             $optgroup.append($item);