Can't get birthday from Google Contacts Data API in Ruby on Rails

I am trying to get a user's contact's birthdays, from Google's data API using the g开发者_JS百科data gem. But even though I use the full feed, it does not include the gContact:birthday element.

I have also tried fetching only one contact, but the birthday element is still missing.

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Turns out, the ruby library has not been upgraded to use the version 3 protocol... Damn...