[ChaosX]

i dont know how it will run if i do so.

[Renblade]

As far as I know you can't. However, you can get (from Cydia) transformer which practically turns your iPod into an iPhone. It's purely cosmetic though.

[Jeckel]

Yes, you can't; I've tried (by accident) and you get an error because of such. But there are things that can make your iPod appear like an iPhone (at least with the software theme).