What steps will reproduce the problem?
1. In Admin, on Comments page OR Dashboard, hit the "Reply" button for a 
comment.
2. Type your reply and Submit.
3. Comment is added properly, but the following message is displayed:

Fatal error: Call to a member function save_settings() on a non-object in 
/home/example.com/public_html/wp-content/plugins/spam-karma/spam_karma_plugin.ph
p on line 958 

My setup has the WordPress files in public_html/wp, the content in 
public_html/wp-content, and the blog itself is at the site root example.com/.

Though it's purely visual (the comment submits just fine), it causes confusion, 
and the person might easily hit Submit multiple times before realizing the 
comments are submitting.