I'm using the recent version of wordbooker.
I'm using Akismet for spam detection.
Since version 2.1.20 I get the follwoing error when I'm deleting spam:
"Warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, 'wordbooker_delete_comment' was given in XXX/htdocs/wordpress/wp-includes/plugin.php on line 403"
When I'm deleting 5 spam messages, I'll get 5 of this message.