diff --git a/message.go b/message.go
index ccd8b55..e611341 100644
--- a/message.go
+++ b/message.go
@@ -68,7 +68,7 @@ func (m *Message) String() string {
 		args += " " + arg
 	}
 	if m.Trail != "" {
-		return fmt.Sprintf(":%s %s%s :%s", m.Pre, m.Cmd, args, m.Trail)
+		return fmt.Sprintf(":%s %s%s :%s", m.Pre, m.Cmd, args, strings.Replace(m.Trail, "%", "%%", -1))
 	}
 	return fmt.Sprintf(":%s %s%s", m.Pre, m.Cmd, args)
 }