In our application we are using ym4r plugin. And today we got strange error in geocoding parsing 
  #<REXML::ParseException: Missing end tag for 'DependentLocalityName' (got "DependentLocality")
Line:
Position:
Last 80 unconsumed characters:
</Locality></SubAdministrativeArea></AdministrativeArea></Country></AddressDetail>
/opt/ruby-enterprise-1.8.6-20080709/lib/ruby/1.8/rexml/parsers/baseparser.rb:330:in `pull'

I've checked the address we were trying to geocode "Olgastrasse 128, 70180 Stuttgart"
and it turns out that XML/KML response is not well formed (ISO-8859-1 characters with UTF-8 encoding header in XML)

Had to patch Geocoding.get to "force" utf-8 on res after read using to_utf8

        url = "http://maps.google.com/maps/geo?q=#{URI.encode(request)}&key=#{api_key}&output=#{output}"

        res = open(url).read
        begin
           res = res.to_utf8
        rescue
        end

        case output.to_sym

After that XML was good and application happy

<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://earth.google.com/kml/2.0">
<Response>
<name>Olgastrasse 128, 70180 Stuttgart</name>
<Status><code>200</code><request>geocode</request></Status>
<Placemark id="p1">
<address>Olgastraße 128, 70180 Stuttgart-Süd, Stuttgart, Germany</address>
<AddressDetails Accuracy="8" xmlns="urn:oasis:names:tc:ciq:xsdschema:xAL:2.0">
<Country><CountryNameCode>DE</CountryNameCode>
<AdministrativeArea>
<AdministrativeAreaName>Baden-Württemberg</AdministrativeAreaName>
<SubAdministrativeArea>
<SubAdministrativeAreaName>Stuttgart</SubAdministrativeAreaName>
<Locality>
<LocalityName>Stuttgart</LocalityName>
<DependentLocality>
<DependentLocalityName>Stuttgart-Süd</DependentLocalityName>
<Thoroughfare>
<ThoroughfareName>Olgastraße 128</ThoroughfareName>
</Thoroughfare>
<PostalCode>
<PostalCodeNumber>70180</PostalCodeNumber>
</PostalCode></DependentLocality>
</Locality></SubAdministrativeArea>
</AdministrativeArea></Country>
</AddressDetails>
<Point><coordinates>9.177973,48.766634,0</coordinates></Point>
</Placemark></Response></kml>