Kasbah, thanks for the comment. Hash tables are easy once you figure out how they work and get over the intimidation they present with their own set of identifiers and aliases. It also seems you don't understand how the -z switch works, which is okay. The -z switch will unset your item after seconds. So doing:

hadd -z $nick jail 10

would be in lamens terms: add jail to $nick for 10 seconds, then delete.