I don't know too much about the situation in Denmark, but here's a suggestion (and everyone else who knows more about this than me, feel free to chime in): she could get an old iPhone (v. 1.0) off of eBay or wherever here, go to Denmark, then go to the Apple Store and ask for an upgrade to the iPhone 3G. She would probably only have to pay the difference (for the handset that is -- no idea about the cell phone plan pricing available in Denmark).
Success is a lousy teacher. It seduces smart people into thinking they can't lose. -- Bill Gates