iPhone 3G Czech keyboard

Enable the Czech keyboard on the iphone

From the home screen
  1. Go to settings - General - International
  2. Select Keyboards
  3. Move the slider for Czech to ON

Now go into any application where you can type, for example Notes and you should see a globe icon next to the spacebar, this will switch your keyboard between whatever languages you have selected.

NB: Smart suggestions / T9 or whatever the dictionary is called on the iPhone is not supposed to work on a non-English keyboard but it does for my Czech one except that it offers English spelling suggestions and the only Czech ones it offers are what it has learnt from me.