We now have production running on 10.6 (including all those extensions), and have seen no more issues at all. So I am assuming it must be fixed in 10.6 at this point.
Somehow I am getting this crash on my compiled 10.6, but I don't get it on packaged 10.6. :(
I've tried this a number of times so I'm not sure how worth it is trying to get to the bottom of the compile difference. But I would like to understand how the compiled version is different. Really the only difference should be the compile options used for postgres.