diff --git a/app/models/setting.rb b/app/models/setting.rb
index 16f59be72..70d8f2be1 100644
--- a/app/models/setting.rb
+++ b/app/models/setting.rb
@@ -97,7 +97,7 @@ class Setting < ActiveRecord::Base
   end
   
   def value=(v)
-    v = v.to_yaml if v && @@available_settings[name]['serialized']
+    v = v.to_yaml if v && @@available_settings[name] && @@available_settings[name]['serialized']
     write_attribute(:value, v.to_s)
   end