Microsoft has always denied it is building it's own phone instead preferring to allow handset manufacturers like HTC do the building for them while they concentrate on the software.

While that isn't likely to change, has dug up pictures of a phone made by Sharp that looks, from the single FCC filed picture remarkably similar to the Turtle phone mock-ups touted around last year.

The rumour goes something like this. Sharp make the phone. They are the same manufacturer of the T-Mobile Sidekick, which in turn is powered by Danger, which in turn was bought by Microsoft in 2008.

Add into the mix some references to the "turtle" name in the Zune MP3 player OS, an expected announcement by Steve Ballmer on Monday for Windows Mobile 7 and you've got yourself an almost legit rumour story for weekend reading.

All eyes are now on Mobile World Congress.