Microsoft is releasing an over the air update for the HTC 8X that stops the phone from switching from a Wi-Fi connection to cellular when its screen times out. The behavior has been a constant thorn in the sides of Windows Phone users since Microsoft released Windows Phone 7 over two years ago. According to WPCentral, a user in Italy confirmed that after updating, a checkbox was available in advanced Wi-Fi settings to "Keep Wi-Fi on when screen times out." The first evidence of the new setting was spotted last week by WPCentral on a different handset, the HTC 8S. The new software also marks the first OTA update to Microsoft’s new Windows Phone 8 platform.

So far, the update hasn't arrived on our own US-based 8X and 8S devices, which could either mean that Microsoft is staggering the rollout, or that US carriers are holding back on the release. It also isn’t clear yet if the update includes VPN support — the other major feature slated for the Apollo Plus update — but we’ll let you know as soon as we hear anything.

Update: WPCentral has some more details on the so-called "Portico" update. Beyond the Wi-Fi fix, it adds at least three new features: the ability to reject calls with an SMS (recently seen in iOS 6), a "select all" SMS function for easier mass deletion, and SMS draft saving for messages you back out of before sending.