[Riim]

Вот как-то так получилось:

Function.prototype.callAsync = function() {
	var self = this, args = $A(arguments), thisObj = args.shift(), elem = document.createElement('div'), done = false;
	elem.onclick = function() {
		if (!done) {
			done = true;
			self.apply(thisObj, args);
		}
	};
	if (document.createEvent) {
		var e = document.createEvent('HTMLEvents');
		e.initEvent('click', false, false);
		elem.dispatchEvent(e);
	} else document.createDocumentFragment().appendChild(elem).fireEvent('onclick', document.createEventObject());
	if (!done) setTimeout(elem.onclick, 15);
};

var $A = function(iterable) {
	if (iterable) {
		var result = [], i = iterable.length;
		while (i) result[--i] = iterable[i];
		return result;
	}
	return [];
};

var testFunc = function() {
	alert('testFunc');
	throw new Error('testFunc');
};

testFunc.method();
alert('global');
testFunc.method();
alert('global');