I don't know if this was a rumor going around or whatever, but iceburgs are definately work, not just the map specific ice but the database iceburgs that mission designers can put it.
I seem to remember someone saying they were not solid... maybe it was just for torpedoes, but anyway, you can definately die if you hit one.
Yes, I did a test, I didn't find this out in a mission.
Cheers,
David