Get Recent Comments problem

Hello, my forum is located in http://cinexl.net/blog, and I’ve installed the get recent comment plugin (http://blog.jodies.de/archiv/2004/11/13/recent-comments/1/) on it. The problem is that, I’ve done everything correctly (I think), and it works, the only problem, is that I can’t get to the admin panel of the plugin in Options/Recent Comments.
I get the following error message:

Fatal error: Cannot redeclare kjgrc_subpage_gravatar() in /home/cinelnet/public_html/blog/wp-content/plugins/get-recent-comments.php on line 23

I’ve installed the gravatar plugin, but I don’t know what the problem is, and I really need the admin plugin panel.

Anyone can help me? Thanks 😉