BuddyPress.org

hiho
i’m not an expert nor a noob one to know why i’ getting this error msgs and how to fix it .. i’m just a regular user…

aight.. i’m getting this error when I activate the plug-in
~

Warning: Missing argument 2 for wpdb::prepare(), called in /home/tibiacar/public_html/wp-content/plugins/achievements/includes/achievements-classes.php on line 676 and defined in /home/tibiacar/public_html/wp-includes/wp-db.php on line 990

Warning: Missing argument 2 for wpdb::prepare(), called in /home/tibiacar/public_html/wp-content/plugins/achievements/includes/achievements-classes.php on line 676 and defined in /home/tibiacar/public_html/wp-includes/wp-db.php on line 990

Warning: Missing argument 2 for wpdb::prepare(), called in /home/tibiacar/public_html/wp-content/plugins/achievements/includes/achievements-core.php on line 453 and defined in /home/tibiacar/public_html/wp-includes/wp-db.php on line 990

Warning: Cannot modify header information – headers already sent by (output started at /home/tibiacar/public_html/wp-includes/wp-db.php:990) in /home/tibiacar/public_html/wp-includes/option.php on line 568

Warning: Cannot modify header information – headers already sent by (output started at /home/tibiacar/public_html/wp-includes/wp-db.php:990) in /home/tibiacar/public_html/wp-includes/option.php on line 569

i’m using wordpress 3.5 (pt_br)
with buddypress 1.6

Can anyone help me?