The handset appears to be a rebadged version of an HTC phone - some websites have suggested 'Feeler', but that shipped in 2004. It's more likely to be HTC's 'Tornado', or a version of it, as this has yet to go on sale.
Whatever its foundation, the HP handset is said to be the iPaq rw4500, if you can believe the screen photos. Interestingly, the device sports a T-Mobile logo on the back, which seems an odd addition for an HP phone, though presumably the carrier has been able to win the branding as a concession from HP. The HP and iPaq logos are clear and crisp on the front of the device.
The pictures clearly show the presence of a 1.3mp camera, and the device is also said to sport Bluetooth 1.2, Wi-Fi, a 320 x 240 display and Windows Mobile 5.0.