Sorry I missed that statement (possibly since it didn't actually state the version
number).
Anyway, I tried the code you supplied with my own calendar and all it does is pop up a JavaScript alter box with the hacker's name in it. That is not quite a critical situation.
I believe (although I could be wrong) that one of the previous bug fixes was to remove any HTML tags from being passed to the script via the command line. Maybe the fix was only made for the calendar.pl file? In any case, running JavaScript code only affects the user's browser, not the script installation itself AFAIK. The same could be done on any web page.
If you have more concerns you should probably bring them to
Scott's attention via email.
JMO
Dan O.