diff --git a/Casks/mucommander-nightly.rb b/Casks/mucommander-nightly.rb
index e81944251..5a8dd6b63 100644
--- a/Casks/mucommander-nightly.rb
+++ b/Casks/mucommander-nightly.rb
@@ -1,4 +1,4 @@
-class MucommanderNightly < Cask
+cask :v1 => 'mucommander-nightly' do
   version '0.9.1-nighly'
   sha256 '020df01bfc2d8aff20933f47fd80443d20b702e18f7a6a562c2bc25b15e9bc15'