aqObject.GetProperties() does not work?

I have this piece of code:

function PropsTest()
{
    var obj = {x:0, y:1};
    var props = aqObject.GetProperties(obj);
    while (props.HasNext())
    {
        prop = props.Next();
        Log.Message(prop.Name);
    }
}

When I run this, I expect it to log x & y, but it does not. If I pause the script, props has a count of 0 (maybe that's normal?)

Am I doing something wrong?