diff --git a/lib/itunes/receipt.rb b/lib/itunes/receipt.rb
index d1a6ffc..9f82022 100644
--- a/lib/itunes/receipt.rb
+++ b/lib/itunes/receipt.rb
@@ -65,7 +65,7 @@ def initialize(attributes = {})
         receipt_attributes[:in_app].map { |ia| self.class.new(:receipt => ia) }
       end
       @is_trial_period = if receipt_attributes[:is_trial_period]
-        receipt_attributes[:is_trial_period]
+        receipt_attributes[:is_trial_period] == "true"
       end
       @itunes_env = attributes[:itunes_env] || Itunes.itunes_env
       @latest = case attributes[:latest_receipt_info]