Missing argument 2 for wpdb::prepare()

Hi and thanks for making the plugin. This is my second try after deactivating all plugins except buddypress. After choosing the file and hitting the submit button for a comment, I get the following errors:

Warning: Missing argument 2 for wpdb::prepare(),
called in [site url]/wp-content/plugins/imagements/imagements.php on line 183
and defined in [site url]/wp-includes/wp-db.php on line 990

Warning: Missing argument 2 for wpdb::prepare(),
called in [site url]/wp-content/plugins/imagements/imagements.php on line 140
and defined in [site url]/wp-includes/wp-db.php on line 990

Warning: Missing argument 2 for wpdb::prepare(),
called in [site url]/wp-content/plugins/imagements/imagements.php on line 140
and defined in [site url]/wp-includes/wp-db.php on line 990

Warning: Cannot modify header information -
headers already sent by (output started at [site url]/wp-includes/wp-db.php:990)
in [site url]/wp-includes/pluggable.php on line 876

The comment is posted but no image is shown with it.

Using WordPress 3.5 and BuddyPress 1.6.2

http://ww.wp.xz.cn/extend/plugins/imagements/