It is reported from FCC that this HTC devices has been tested under 2G network of AT& T and T- Mobile . It takes the 850/1900 GSM system rather than WCDMA.

Under normal circumstance, when the Phone arrived & ready for testeing at FCC, the mobile systems will not released to the public soon, However this time HTC seems to be very eager to uncover what the systems it takes. From this document, obviously this is windows phone, whose name code is PI39110, and it also supports Wifi. Probably this window phone may carry the long expecting Mango System.

All of us know that till now no Mongo mibile phone is official released by HTC. However from the documents, This kind of mobile phone named as PI39110 possibly is the long-time rumoured HTC Eternity.