Those that updated to Android 4.2 might have noticed a bug that prevents users from selecting December for events like birthdays inside of the People app. Google has now officially addressed the issue in a post on the Android Google+ page by confirming that it plans to fix the bug before December:
We discovered a bug in the Android 4.2 update, which makes it impossible to enter December events in optional fields of the People app (this bug did not affect Calendar). Rest assured, this will be fixed soon so that those of you with December birthdays and anniversaries won’t be forgotten by your friends and family.
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