This plugin works great for me with Trac V0.11.7 for comments added through Trac itself. Recently I started using Mylyn inside of Eclipse to create and add comments to Trac tickets. It generally works well, but for some reason comments added through Mylyn can't be edited using this plugin; I just get a message like:
Ticket change '1' not found. Please try again.
I can add a following comment to the same ticket through Trac and edit it (in this example as change '2') without problems. I suppose the "problem" could be in Mylyn, but since it shows up only when using this plugin, I am not sure how to report it there.