Forum OpenACS Q&A: Response to Security: Hacker sends Viruses
You'll also need the Tcl Standard Library. The latest, as of this writing, is version 0.8 and can be found at dev.scriptics.com (which is in the process of moving to tcl.activestate.com). The Tcl standard library requires Tcl 8.2 or higher. If you only have Tcl 8.0 you'll need to upgrade. (Source, binaries, and RPMs of Tcl 8.3.3 are available from ActiveState.)
Then, it's basically just a matter of making it executable and running it. emdia -? will give you a list of available command line options, as well as their defaults. I run emdia nightly in my crontab with the following options:
emdia -email firstname.lastname@example.org -mailhost 10.1.2.2 -ftp-subdir /6.2/en/os/i386 -target /var/emdia -notify-on-abortI explicitly set the ftp-subdir, because I'm running RH 6.1, but all the 6.x security & bug fix updates end up in the 6.2 subdirectories on RH's site.
If you have any questions/problems, let me know.