From Stefano's email:

1. go get a subversion client (at http://subversion.tigris.org)
2. checkout the timeline project from the URL

   http://simile.mit.edu/repository/timeline/trunk/

   NOTE: this is the *latest* version, not the one currently available on the web site, so you might want to try that in your page first.

3. change what you want from your local copy
4. open your shell or windows prompt
5. go to the directory where your local copy of timeline resides
6. type "svn diff > patch.txt" or equivalent for your subversion client
7. file a jira report at

   http://simile.mit.edu/issues/browse/TIMELINE

   and attach your patch (if you send it here, it might get lost and forgotten in the flow of email, in jira it stays there visible at all times).