I saw in the locked post with almost the same name that people had been searching in vain for the solution that Kieran mention. That version is probably mine, so i thought i might as well make iy available for everyone.

I made an edited version of the Calendar that solves this problem ( if you write {CALENDAR 1,4} only events from the calendar with id 1 and 4 will be displyed.

My advise is to wait for the next version from Kieran, but i made my edited version available at
http://www.likabra.se/calendar_hack.php

Regards
Rickard Stjernqvist

I have modified the title of this thread and have stuck it to the top of the forum so that people who are looking for it may use it if they can't wait for the next release.

As Rickard suggests however, you are better off waiting for this functionality to be officially released.