$conf .= "auth_param basic program " . SQUID_LOCALBASE . "/libexec/squid/basic_ldap_auth -v {$settings['ldap_version']} -R -b "{$settings['ldap_basedomain']}" -D {$settings['ldap_user']} $password -f "{$settings['ldap_filter']}" -u {$settings['ldap_userattribute']} -P -h {$settings['auth_server']} -p $port\n";

Adding the -R for "Do not follow referrals", -h server  LDAP server (defaults to localhost),
and -p port. It was originally just -P {$settings['auth_server']}:$port\n which didn't seem to work. I also put the quotes around the basedomain as I saw this configuration somewhere else, not sure if that is needed or not but it works so I am not going to change it.
I hope this helps you all with Squid3-Dev and LDAP.