ISC makes dhcpd and BIND.
Dhcpd can update a BIND zone using a variety of methods. The one I saw examples of is called the "interim" method. It requires that you create what's called a TISC key, used by BIND to authenticate the zone update requests.
All fine and dandy. BIND even has a tool to generate such keys.
Too bad about 1 in every 8 times, the key will include a / and will be a syntax error if you include it in a BIND named.conf file.
A minor bug? Sure. But come on, noone has noticed it?????