While ES5 doesn't have ES4/ActionScript classes, some of the features it introduces (like Object.freeze) are explicitly design to support classical inheritance,

While ES5 doesn't have ES4/ActionScript classes, some of the features it introduces (like Object.freeze) are explicitly design to support classical inheritance, and the ES "Harmony" project will probably build more classical OOP syntax into the next version, on top of the new ES4 semantics.