function win(uri,name,features) { //v2.0
  window.open(uri,name,features);
}

function act(n) {
  eval("document.images." + n + ".src = " + n + "_on.src");
}
function deact(n) { 
  eval("document.images." + n + ".src = " + n + "_off.src");
}

function preload(prefix,pic_array,extension) {
  for (i = 0; i < pic_array.length; i++) {
    eval(pic_array[i] + '_off = new Image;');
	  eval(pic_array[i] + '_on = new Image;');
		eval(pic_array[i] + '_down = new Image;');
	  eval(pic_array[i] + '_off.src = "' + prefix + '/' + pic_array[i] + '_off.' + extension + '";');
	  eval(pic_array[i] + '_on.src = "' + prefix + '/' + pic_array[i] + '_on.' + extension + '";');
		eval(pic_array[i] + '_down.src = "' + prefix + '/' + pic_array[i] + '_down.' + extension + '";');
  }
}
//to change
preload('/nav', new Array('bt_news','bt_about','bt_team','bt_marken','bt_service','bt_kontakt','bt_copyright'), 'gif');
preload('/nav', new Array('bt_geschaeft','bt_geschichte','bt_chronologie','bt_helmut','bt_gertraud','bt_ingrid','bt_uhren','bt_goldschmuck','bt_silberschmuck','bt_stahlschmuck','bt_sonstiges','bt_goldschmiede','bt_uhrwerk','bt_engelbert_kathi','bt_monja_sandra'), 'gif');
//preload('nav', new Array('bt_copyright'), 'png');