Experimentar:http: //maps.googleapis.com/maps/api/geocode/json? address = Otrbottyán, Hungria & sensor = true

No iPhone 4 e simulador,

 -(void)requestFailed:(ASIHTTPRequest *)request {
   NSLog(@"geocode fail code: %d",[request responseStatusCode]);
   NSLog(@"geocoding failed: %@",[request responseString]);
}
2011-06-01 11:36:27.343 app[1174:307] geocode fail code: 0
2011-06-01 11:36:27.345 app[1174:307] geocoding failed: (null)

Em um navegador, recebo:

   "results" : [
    {
    "address_components" : [
        {
           "long_name" : "Őrbottyán",
           "short_name" : "Őrbottyán",
           "types" : [ "locality", "political" ]
        },
        {
           "long_name" : "Pest",
           "short_name" : "Pest",
           "types" : [ "administrative_area_level_1", "political" ]
        },
        {
           "long_name" : "Hungary",
           "short_name" : "HU",
           "types" : [ "country", "political" ]
        }
     ],
     "formatted_address" : "Őrbottyán, Hungary",
     "geometry" : {
        "bounds" : {
           "northeast" : {
              "lat" : 47.7138950,
              "lng" : 19.34353090
           },
           "southwest" : {
              "lat" : 47.63339999999999,
              "lng" : 19.2051070
           }
        },
        "location" : {
           "lat" : 47.6846190,
           "lng" : 19.2883260
        },
        "location_type" : "APPROXIMATE",
        "viewport" : {
           "northeast" : {
              "lat" : 47.7138950,
              "lng" : 19.34353090
           },
           "southwest" : {
              "lat" : 47.63339999999999,
              "lng" : 19.2051070
           }
        }
     },
     "types" : [ "locality", "political" ]
  }

], "status": "OK"}

Outros pedidos com caracteres ingleses padrão neles funcionam e retornam corretamente no dispositiv