@docfish - I cannot say this strongly enough, DO NOT HACK CORE. If this is a change that absolutely must be made, create a patch and submit it on Trac. If this is a minor change that will fix just your installation but doesn't belong in core, write a plugin.
If you hack core files, you will lose your changes whenever you update WordPress. If the code you changed really did fix a bug, you lose your bug fix whenever you update and no one else benefits from your work.
You did the right thing by opening a Trac ticket to report the issue. But once you open a bug report, you have to follow up with it. Other developers will ask questions to clarify the issue, and developers will create patches you can test to see if they fix the issue.
If a patch fixes the issue, and the patch is in Trac, there's a good chance a member of the core team will commit the changes - which means the next version of WordPress won't have that bug.