att PDA iphone plan

[skd006]

I was wondering if it is possible to buy an iphone for example in Hong Kong where they are sold unlocked. Since, i am already and att user i wanted to add a line just with a pda data plan, without telling them i am using it for an iphone.
I do not want a voice plan already have a blackberry for that, or do you have any other suggestions of how i could use iphone with data only
would this work?

 

[Applejuiced]

I dont know if a PDA wireless cards sim would work inside the iphone just for data but not phone use.