Display service links in comments area

Giving an option of attaching service links to comments would be a great feature as I'm having problems displaying service links in comments area.
I'm using advanced forum and it would be nice to have service links display in each thread. I did quite a lot research on how to modify theme template files but can't seem to be able to display in comments area.
Adding preprocess function to templete.php and then using API to print in certain area works but can't seem to do that in comments area. Most likely I'm not finding the right spot where the code should go.
Help, add feature, or close it - thanks for the great module