Rails3 Google Maps使用selenium进行测试

I'm trying to test a google maps app with Rails3. I'm using cucumber with capybara and selenium for JavaScript testing. I have a map where I wait for google maps to be loaded, and then send an ajax request to my server, where I get locations that I'm inserting into the map. I'm wondering if it's possible with selenium to wait until google maps is loaded, the ajax call to my server is finished and the marker are placed inside the map. The other issue is, how to select this marker within google maps. Are there any selectors?I'm trying to test a google maps app with Rails