Google Maps recently (July 2013) upgraded the Google Maps platform (http://www.google.ca/maps/about/explore/). This new platform has display issues (map will not render) when using ICAP scanning (request and/or response)
Disable ICAP scanning for Google Maps
To disable request scanning for google maps
<cache>
url.domain=maps.google.com request.icap_service(no)
To disable response scanning
<cache>
url.domain=maps.google.com response.icap_service(no)
To disable both
<cache>
url.domain=maps.google.com response.icap_service(no) request.icap_service(no)