diff --git a/samples/client/petstore/ruby/spec/api_client_spec.rb b/samples/client/petstore/ruby/spec/api_client_spec.rb
index 054f63bc4ef..7b2478ea67c 100644
--- a/samples/client/petstore/ruby/spec/api_client_spec.rb
+++ b/samples/client/petstore/ruby/spec/api_client_spec.rb
@@ -158,6 +158,7 @@ describe Petstore::ApiClient do
 
       api_client.json_mime?('application/xml').should == false
       api_client.json_mime?('text/plain').should == false
+      api_client.json_mime?('application/jsonp').should == false
     end
   end