LoadVars.prototype.mySendAndLoad = function(url, response, method) {
	LoadVars.prototype._toString = LoadVars.prototype.toString;
	LoadVars.prototype.toString = function() {
		return unescape(this._toString());
	};
	ASSetPropFlags(LoadVars.prototype, "_toString", 3);
	this.sendAndLoad(url, response,  method);
	LoadVars.prototype.toString = LoadVars.prototype._toString;
};
ASSetPropFlags(LoadVars.prototype, "mySendAndLoad", 3);
// --------------------------------
sendData = new LoadVars();
sendData.ok_page = "データ1";
sendData.to_mail = "データ2";
response = new LoadVars();
response.onLoad = function(ok){
	trace(ok);
}

sendData.mySendAndLoad("xxxx.cgi",response,"POST");