I had some conversation with the Oracle Calendar crew about this when I was in Montreal last summer, and they assured me that it was a known problem that would eventually get fixed.
I hadn’t thought about it for a while, but while I was out on vacation last week Kathy Christoph from the University of Wisconsin dropped a note to say she was trying to import some ical data from the Educause Conference Itinerary Builder into Oracle Cal and was having problems, and asked if I had any advice.
At the time I wrote a short Python script to handle converting data back and forth, but it looks like I didn’t save that when I changed to the new iMac G5 last month.
So being a curious type, I installed a recent version of the Oracle Calendar client, version 10.1.1 and tried importing data from Educause. And it worked!
So thanks to Kathy for prodding me into looking at this again, and thanks to the Oracle crew for making progress in interperability!