diff --git a/doc.go b/doc.go
index c17ec07..3c4515e 100644
--- a/doc.go
+++ b/doc.go
@@ -6,4 +6,4 @@
 package mail
 
 // VERSION is used in the default user agent string
-const VERSION = "0.3.0"
+const VERSION = "0.3.1"