After searching for the ArrayIndexOutOfBoundsException, I found https://bugs.launchpad.net/ubuntu/+source/gcj-4.4/+bug/487922 which seems quite closely related. However, natty comes with gcj-4.5, not 4.4, and apparently a fix for that problem was released. So either that fix got discarded somewhere on the way to natty, or it no longer fixes this issue.
After searching for the ArrayIndexOutOf BoundsException , I found https:/ /bugs.launchpad .net/ubuntu/ +source/ gcj-4.4/ +bug/487922 which seems quite closely related. However, natty comes with gcj-4.5, not 4.4, and apparently a fix for that problem was released. So either that fix got discarded somewhere on the way to natty, or it no longer fixes this issue.