It doesn't apply directly to the Facebook app, but you can have Google calendar automatically sync your Facebook Birthdays and events. Then they will show on your android device calendar when your calendar syncs to your phone. This should be a continuous sync and not a one time sync.
Its a workaround to the original poster's problem and the only way to sync to my knowledge on android.
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20 Sep 2014
By Tomek Kondrat
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