Comment 4 for bug 367157

Yeah, those files might have helped :) Just not sure if the archive was gzip'd...

Don't think this is a generic problem. I installed squid on a fresh 8.10, did a do-release-upgrade to Jaunty, and Squid was still working. Of course, that was with only the default configuration.

Looking in your /var/log/dist-upgrade/term.log I see quite a few attempts to access the non-existent path /null. At one occasion it happens right next to your "subprocess post-installation script returned error exit status 1".

Can you find anything in your squid configuration which would explain why the upgrade would want to access /null?