Object property constants in ECMAScript?

Question

I've seen some proposals for ECMAScript Harmony in terms of being able to specify constants with the keyword const. However, it seems to be only available in block scopes (i.e., FunctionBody and Program). Is there a way to define constants as an object property (imagine myObj.STATUS_OK)?

I guess the suggested way is to use properties via Object.definePropert(y/ies), but that does not seem very convenient, now is it?