How to print a custom user field in comment.tpl.php?
I've got it working! I've used user_load($comment->uid) to load the author relationship.

I placed the code in a copy of comment.tpl.php in my sub theme.

&lt;?php print render(field_view_field('user',user_load($comment-&gt;uid), 'YOUR-CUSTOM-USER-FIELD'));?&gt;


Cheers and good luck!