The latest iCal update: 1.5.4

I just noticed on Apple's site that they've updated iCal to fix a potential security vulnerability: iCal 1.5.4: What's an "unsafe" alarm?

iCal 1.5.4 displays an "unsafe" alarm alert when you try to import a calendar that contains existing alarms that open documents or other applications.

So I clicked on Software Update... lo and behold, there it was. So take a few seconds, fire up Software Update and patch your iCal.