2 files changed, 16 insertions, 0 deletions
diff --git a/README.md b/README.md
index fa87603..c494ef5 100644
--- a/README.md
+++ b/README.md
@@ -59,8 +59,20 @@ environment variables)
 % REMOTE_IMAP_HOST=imap.coolmailsite.example REMOTE_SMTP_HOST=smtp.coolmailsite.example olden-mail
 ```
 
+## Middleware
+
+In order to work with some older clients, middleware allow transformation of
+messages. The current middleware are:
+
+- `FindMailboxesCompatibility` - Transforms IMAPv3 FIND MAILBOX commands to
+    IMAPv4 LIST commands.
+
 ## Debugging
 
 You can control how much it prints by setting `RUST_LOG`. Setting it to
 `debug` will output the whole protocol stream. The default level is
 `info`.
+
+Messages coming from the client are prefixed with `>>>`, and messages coming
+from the server with `<<<`. If a middleware modified a command, you'll see
+the message that was actually sent prefixed with `###`.
diff --git a/src/middleware/find_mailboxes_compatibility.rs b/src/middleware/find_mailboxes_compatibility.rs
index daf0dc0..42db396 100644
--- a/src/middleware/find_mailboxes_compatibility.rs
+++ b/src/middleware/find_mailboxes_compatibility.rs
@@ -56,6 +56,10 @@ impl Middleware for FindMailboxesCompatibility {
                     }
                 }
 
+                if line.contains("OK") {
+                    return Some("{tag} OK MAILBOX Completed.".to_string());
+                }
+
                 Some(line.to_string())
             })
             .collect();