Intermittent segfault in var_hrswrun

I am running Ubuntu 8.04.3 LTS, upgraded from 6.06 LTS. At intermittent times, snmpd dies with a segfault. Once I restart it, snmpd behaves normally, but will eventually die again. The interval between starting snmpd and having it die by segfault can be as small as an hour and as large as 3 weeks. I have a backtrace from the most recent segfault, which I am attaching. The version of snmpd and libsnmp15 used to generate the backtrace is 5.4.1~dfsg-4ubuntu4.3, which is currently in hardy-proposed.

I originally thought that this was part of bug #200614, as I was seeing the same problem. That is why I am using the hardy-proposed version of snmpd, is because I thought it would fix the segfaults. However, the fix for bug #200614 does not fix this segfault problem for me; when I brought it up in the bug (bug #200614 comment 18), I was told that it was probably not related (bug #200614 comment 19), and that I should submit a new bug, which I am doing now!