the geocache.xml file is generated by the map js file.
it is updated any time there are new addresses.
If a new address is added to the database, the map js file will connect top the google geocoder to lookup the the latitude and longitude for that address, then update the XML file so it will not need to connect to the geocoder the next time the page is loaded.
I cant say how that line got messed up to be honest, but you should be able to go to the xml file in the browser:
and not see any errors.