Wirelessly posted (BlackBerry8530/5.0.0.601 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)

What class of service? AA flies to ZRH on its own metal, but not to Croatia; for that, you'd have to use a partner carrier. If you Google the Croatian airport(s) you are considering, you should find the airport's Wikipedia entry, which typically lists available airlines and destinations. Then, your challenge will be finding partner award seats for summer travel.