Do not modify standard symbol in JSON behaviour. It seems to be good now

spec/symbol_spec.rb

@@ -1,11 +1,16 @@
 require 'spec_helper'
 
+#TODO, is this really a good behaviour?
 describe Symbol do
   it 'to_json becomes a string in json format' do
-    :abc.to_json.should == 'abc'
+    :abc.to_json.should == '"abc"'
   end
 
   it 'as_json becomes a string in json format' do
     :abc.as_json.should == 'abc'
   end
+
+  it 'works in hashes' do
+    expect([{abc: :def}].to_json).to eq %|[{"abc":"def"}]|
+  end
 end