[Plugin: WP-PostViews] Header already sent

Notice: Undefined index: postviews_id in /home/asianp/public_html/my/wp-content/plugins/wp-postviews/wp-postviews.php on line 648

Warning: Cannot modify header information – headers already sent by (output started at /home/asianp/public_html/my/wp-content/plugins/wp-postviews/wp-postviews.php:648) in /home/asianp/public_html/my/wp-includes/pluggable.php on line 866

http://wordpress.org/extend/plugins/wp-postviews/