Really, the best way to do this is to write your own client. It's pretty straightforward; just model it after the scripts in /sbin/e-smith/dynamic-dns. The client specs are at
http://www.dtdns.com/specs.txtIf you edit /sbin/e-smith/dynamic-dns/custom, and add this line under "Your handler starts here", I think it should work (but this is just a guess based on the specs page):
wget
http://www.dtdns.com/api/autodns.cfm?id=$DOMAIN&pw=$PASSWD&ip=$IPADDR
This should be all on one line, and you'd need to set your domain to dirtypenguin.darktech.org in the console configuration. You'd set the dynamic dns service to "custom", you could use anything for the userid, and the password would be your password. This script will then be called whenever the IP address of your e-smith box changes.