I've found information on how to keep squid from caching domains/IP addresses, however, that's not quite what I want. I'd like to prevent it from caching .jnlp and .jar files.
The core problem being that when I push updates out to our server, our users that are behind a squid proxy may not get the updated version for several days (apparently it takes that long for squid to figure out that the files have changed). Perhaps I've missed an even easier solution?