No it never has worked, but many other apps that I use that sync with iCal can also sync with the calendars from exchange.
In Omnifocus even though in iCal I have 5 Calendars, the only one that Omnificus sees are local calendars. Remote calendars are not available in Omnifocus for syncing.
I do have other apps that sync with iCal that can see all the other calendars and sync with them. (THL, and Things).
I can set you up an exchange account for testing if you all like.