The latest version of Android sports a pretty embarrassing bug that you'll notice if you have any friends or family with birthdays in December.
The contacts app jumps straight from November to January - no matter what year - whether you're using it on a smartphone or a tablet.
This rather staggering omission was first spotted by the Android Police website a couple of days ago - and has since been verified by every tech site with access to an Android 4.2 device, including T3.com.
Any existing saved dates will be display as normal - and the separate Google Calendar is also unaffected because this is a coding error in the date picker display input rather than the memory.
According to reports, Google is aware of the fact it left out a month, and has reviewed the issue. But the company will still need to put out a new update and post it to carriers before the problem can be corrected.
Chances are Google will be quick out the door with Android 4.2.1. But in the meantime, it's probably best to avoid making friends with anyone born in December.