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HTML

<select name="country" id="country"></select>
<select name="state" id="state"></select>

JavaScript

// Countries
var country_arr = new Array("Afghanistan", "Albania", "Algeria", "American Samoa", "Angola", "Anguilla", "Antartica");

// States
var s_a = new Array();
s_a[0]="";
s_a[1]="Badakhshan|Badghis|Baghlan|Balkh|Bamian|Farah|Faryab|Ghazni|Ghowr|Helmand|Herat|Jowzjan|Kabol|Kandahar|Kapisa|Konar|Kondoz|Laghman|Lowgar|Nangarhar|Nimruz|Oruzgan|Paktia|Paktika|Parvan|Samangan|Sar-e Pol|Takhar|Vardak|Zabol";
s_a[2]="Berat|Bulqize|Delvine|Devoll (Bilisht)|Diber (Peshkopi)|Durres|Elbasan|Fier|Gjirokaster|Gramsh|Has (Krume)|Kavaje|Kolonje (Erseke)|Korce|Kruje|Kucove|Kukes|Kurbin|Lezhe|Librazhd|Lushnje|Malesi e Madhe (Koplik)|Mallakaster (Ballsh)|Mat (Burrel)|Mirdite (Rreshen)|Peqin|Permet|Pogradec|Puke|Sarande|Shkoder|Skrapar (Corovode)|Tepelene|Tirane (Tirana)|Tirane (Tirana)|Tropoje (Bajram Curri)|Vlore";
s_a[3]="Adrar|Ain Defla|Ain Temouchent|Alger|Annaba|Batna|Bechar|Bejaia|Biskra|Blida|Bordj Bou Arreridj|Bouira|Boumerdes|Chlef|Constantine|Djelfa|El Bayadh|El Oued|El Tarf|Ghardaia|Guelma|Illizi|Jijel|Khenchela|Laghouat|M'Sila|Mascara|Medea|Mila|Mostaganem|Naama|Oran|Ouargla|Oum el Bouaghi|Relizane|Saida|Setif|Sidi Bel Abbes|Skikda|Souk Ahras|Tamanghasset|Tebessa|Tiaret|Tindouf|Tipaza|Tissemsilt|Tizi Ouzou|Tlemcen";
s_a[4]="Eastern|Manu'a|Rose Island|Swains Island|Western";
s_a[5]="Andorra la Vella|Bengo|Benguela|Bie|Cabinda|Canillo|Cuando Cubango|Cuanza Norte|Cuanza Sul|Cunene|Encamp|Escaldes-Engordany|Huambo|Huila|La Massana|Luanda|Lunda Norte|Lunda Sul|Malanje|Moxico|Namibe|Ordino|Sant Julia de Loria|Uige|Zaire";
s_a[6]="Anguilla";
s_a[7]="Antartica";

var selectCountry = 'country';
var selectState = 'state';

populateCountries(selectCountry, selectState);

function populateStates( countryElementId, stateElementId ){

    var selectedCountryIndex = document.getElementById( countryElementId ).selectedIndex;

    var stateElement = document.getElementById( stateElementId );

    stateElement.length=0;  // Fixed by Julian Woods
    stateElement.options[0] = new...