crazy var reference behavior on Android 2.3.6

gistfile1.js

function func(firstarg){
  console.log(firstarg); // on Chrome it's defined, on Android 2.3.6 browser it's defined
  var args = Array.prototype.splice.call(arguments, 0, arguments.length);
  console.log(arguments[0]); // on Chrome it's undefined, on Android 2.3.6 browser it's undefined
  console.log(firstarg); // on Chrome it's defined, on Android 2.3.6 browser it's *undefined*
}

func("hello");