The information below explains how to change the return URL in Trackback. The example looks exactly like what I need to do on my own site. But when I try to enter the example code in my preferences I'm only allowed to enter the first 40 characters into the preference field.

Return URL's

When a trackback ping is sent to another site, a URL must be included which links back to your message. Typically, you'd just point it back to your message's canonical URL, but you might want to customize it for your site.

Most macros and resources will work. Here's an example that would point at your fullThread page.

<!--#siteUrl-->fullThread$msgnum=<!--#msgNum msgNum="top"-->#msg<!--#msgNum-->

Perhaps this is a bug, or perhaps I'm doing something wrong.

Cordially,
- twf