I couldn't find a way to make CC give the correct URL to users when running in a configuration like below:
ProxyPass / http://localhost:8080/
ProxyPassReverse / http://localhost:8080/
CC would insist on building URLs using localhost:8080 even though the user can only access via http://your.host.com/. With the patch CruiseControl will use the X-Forwarded-Host HTTP header to build the correct address.