We have now made available next 4.6 build of Diladele Web Safety with additional NTLM authenticating helper for Squid that allows to do the Negotiate/NTLM and pure NTLM authentication on your proxy without need to install and manage Samba and/or join machine to the Active Directory domain. It is now possible to use the proxy not only from domain joined machines but from all your network as long as the user knows his AD credentials.
Build is at http://quintolabs.com/soon.php, docs with rewritten Active Directory integration tutorial at http://docs.diladele.com/administrator_guide_4_6/active_directory/index.html.
Please take a look and share your experience – hope it will make the life of the network admin a little easier.
Diladele Dev Team