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So maybe I am missing something, but it seems that ZCS does not support any sort of To-Do items. This seems like a glaring omission; lots of things on a calendar are not appointments: "Call Fred Foo at 8 AM tomorrow" usually works better as a to do with an alarm than as an appointment cluttering up the calendar.
It's actually in the OS beta's-as you can see from pmweb (v5.0 is here) there's a bunch more work to be done on tasks and IM but they're making progress daily!
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