Geotargeting doesn't work with special characters.
In GeoIP.delivery.php line 80, added:
$ret = array(
'country_code' => 'CH',
'region' => 25,
'city' => "Z".chr(252)."rich",
'latitude' => 47.3667,
'longitude' => 8.55
Same rule in delivery limitation for Country/City with "is equal". Result - ad is not displayed. It's probably because of problems with encodings.