diff --git a/README.md b/README.md
index 1bdd732..f5ba34c 100644
--- a/README.md
+++ b/README.md
@@ -95,7 +95,7 @@ Bugs, issues and contributions can be requested to both the mailing list or the
 * Python v2.7+
 * Python v3.4+ ***[STALLED] (experimental: [see known issues](https://github.com/OfflineIMAP/offlineimap/issues?q=is%3Aissue+is%3Aopen+label%3APy3))***
 * six (required)
-* imaplib2 >= 2.55 (optional)
+* imaplib2 >= 2.57 (optional)
 
 
 ## Documentation