The Windows Phone messaging hub is disabled by sending certain a text string, according to the Winrumors blog

A reported vulnerability in Windows Phon causes its messaging features to be disabled after the device is sent a specific SMS or chat message.

The bug was reported to the blog Winrumors by Khaled Salameh, wrote Tom Warren, who runs the Microsoft-focused website. Warren wrote that both are in the process of notifying Microsoft.

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In a video, Warren shows that after a Windows Phone device receives the message, it then shuts down. Upon reboot, the messaging hub tile does not work despite repeated attempts. The denial-of-service issue also occurs if a person is sent a specific Facebook or Windows Live Messenger chat message.

Winrumors ran tests on the HTC Titan, the Samsung Focus Flash and others running the 7740 version of Windows Phone 7.5 and the Mango RTM build 7720, Warren wrote. "At this stage, there doesn't appear to be a workaround to fix the messaging hub apart from hard resetting and wiping the device," he wrote.

The bug appears to have other strange effects. Warren found that a live tile featuring updates from a Facebook friend will lock up if that friend posts a particular message. Warren wrote that problem could be avoided by initially booting up a device, getting past the lock screen quickly and then removing the live tile before it flips over and locks the device.

Fujitsu Toshiba IS12T Lauched First Windows Phone 7.5

HTC Titan stand down, Samsung Omnia W step aside, there's only one handset that can lay claim to being the first ever Windows Phone 7.5, aka Mango, device and it's the Fujitsu Toshiba IS12T - a smartphone born out of a partnership between the two Japanese electronics giants.

The IS12T was announced back in July and takes its design inspiration from a Japan-only Android handset, the Regza T-01C, but the phone is proof that copying isn't always a bad thing to do.

And that's because it's a lovely looking handset, that looks almost fourth-gen iPod nano-esque with its brightly coloured brushed aluminium finish (yellow, pink or black), with a rubber black trim thrown in for a bit of ruggedness.

And, rugged it is - the phone is both water and dust proof - although we didn't fully test those claims out. We don't think the DoCoMo rep would have liked it if we'd dunked it in our drink.

This toughness doesn't seem to come at a cost either. The IS12T is fairly lightweight at 113g and measures a less-than-bulky 118 x 59 x 10.6mm, with a 3.7-inch, 480 x 800, LCD capacitive touchscreen packed in too.

But it's the spec sheet that really stands out. Whilst it doesn't quite reach the crazy heights of the HTC Titan's 1.5GHz power - it packs a 1GHz Qualcomm Snapdragon MSM8655 along with Adreno 205 graphics - it blows the Windows Phone competition out of the water when it comes to the camera.

In fact, it blows pretty much any smartphone out of the water in this area. It packs a 13.2-megapixel autofocus snapper with an LED flash, CMOS sensor and boasts 720p HD video recording too.

There's no front facing camera though, which is a bummer with the video conferencing facilities afforded by Mango, but it does contain a very healthy 32GB of onboard storage.

There are no plans for a release outside of Japan, which is a damn shame as the IS12T is an absolutely gorgeous Windows Phone 7 handset. However, it is a global phone with both GSM and  CDMA onboard, so you could always get one shipped in if it has really taken your fancy.

It's available in Japan through DoCoMo now.

Samsung Focus S (AT&T) Review

Those who doubted that Windows Phone isn't a mobile platform to be reckoned with need to check out the new Samsung Focus S for AT&T. Equipped with a fast 1.4-GHz CPU, a vibrant 4-inch Super AMOLED Plus screen, and all the goodness of Windows Phone 7.5, this handset has a lot going for it. Best of all, you can now snag this smartphone for $99, much less than the $199 launch price.

Like a Galaxy S II in Windows clothing, the Samsung Flash S looks very similar to its Android kin. Its front is a smooth slab with gentle curves and rounded edges, and the back has a slight chin at the bottom. On the front is a large 4.3-inch display, framed by a 1.3-megapixel camera and an earpiece above and three capacitive buttons (Back, Search, Windows) below it.

Flat and extremely thin, the Flash S (4.9 x 2.6 x 0.3 inches) sports a marginally smaller profile than the Galaxy S II (5 x 2.6 x 0.4 inches). At a feather-weight 3.9 ounces, this Windows Phone is almost a full ounce lighter than the HTC Radar (4.8 ounces), and a hair lighter than the Galaxy S II and even the diminutive Samsung Focus Flash (both 4.1 ounces).

Of course, the Focus S is much wider than the Focus Flash, its smaller 3.7-inch Windows sibling. The Focus S is less of a fingerprint magnet too, thanks to a textured back plastic battery cover--the Flash's battery door is brushed metal. Similar to the Galaxy S II, the thin cover of the Focus S feels flimsy and flexes easily.

Also on back is the 8-MP main camera and LED flash and speaker. A headphone jack sits on the handset's top edge, while camera and power buttons occupy the right. The bottom lip holds a microUSB port and a thin volume rocker runs along the left side.