Userextra/ usermeta plugin

I have got a question about creating a PHP function code with this plugin. I asked the same question on the plugins support site, but never got a response, so that’s why I decided to try over here. Therefore this question is only for the people who use this particular plugin and know a bit of php programming.

My question is:

can anybody construct a php code to do the following:
In my comments.php I want a particular field from the Extended profile form added next to the users name, but only when that user filled the field on his profile.
So basically its like the comment_author_link, but for an extended field.

Can anybody help me?