javascript - JSON left out Infinity and NaN; JSON status in ECMAScript?

Any idea why JSON left out NaN and +/- Infinity? It puts Javascript in the strange situation where objects that would otherwise be serializable, are not, if they contain NaN or +/- infinity values.

Looks like this has been cast in stone: see RFC4627 and ECMA-262 (section 24.5.2, JSON.stringify, NOTE 4, page 683 of the ECMA-262 pdf at last edit):

Finite numbers are stringified as if by calling ToString(number). NaN and Infinity regardless of sign are represented as the String null.