need help with org-mac-iCal and long-standing recurring events

[Doug Hellmann <doug.hellmann@gmail.com>]

I've submitted a couple of patches to org-mac-iCal recently, but this  
latest problem is beyond my lisp skills to fix.

org-mac-iCal imports entries from iCal into the diary so they can be  
displayed in org-mode's agenda views.  It limits the imported entries  
based on a date range managed org-mac-iCal-range so that the diary is  
not full of old items, slowing down processing.

The date range filtering does not take recurring events into account,  
though.  If the date range is set to eliminate items older than 1  
month and a recurring item started 2 months ago, it is ignored.  This  
is true even if the event has no end-date set and it would recur  
within the desired date range.

The function in question is omi-import-ics in contrib/lisp/org-mac- 
iCal.el.  I *think* the section I need to modify starts on line 168:

	(when (or
	       (and
		(= yearEntry year)
		(or (< monthEntry (- month (/ org-mac-iCal-range 2))) (> monthEntry  
(+ month (/ org-mac-iCal-range 2)))))
	       (< yearEntry (- year 1))
	       (> yearEntry (+ year 1))
	       (and
		(= yearEntry (- year 1)) (/= monthEntry 12))
	       (and
		(= yearEntry (+ year 1)) (/= monthEntry 1)))
	  (delete-region startEntry endEntry))))

As a first attempt, I tried changing the filtering so that events with  
an RRULE property set (indicating a recurrence rule) are always  
imported into the diary, but somehow managed to introduce an infinite  
loop to the filter.

So I'm looking for someone with better lisp skills who can advise me  
about trying to fix the problem I describe above.  Any takers?

Thanks,
Doug