Ubuntu Dapper - using daemons, not inetd. How to make blockhosts run?

I'm using ubuntu dapper drake. I've set up blockhosts 2.0.5, and when run manually it seems to work fine. However it does not appear to be executed when a SSH login is made. I cut & pasted from the INSTALL file into hosts.allow.

I notice that dapper doesn't use inetd for ssh, ssh is run as a daemon on startup - which suits me fine - however is this is why blockhosts isn't working? If so, what's the best way to use blockhosts? Execute blockhosts from cron? How often?