Network Activate BuddyPress

I have installed the multisites and have my network running. However, when I activate buddypress network activation, it shows this error:

Fatal error: Cannot redeclare bp_dtheme_ajax_querystring() (previously declared in /home/antitalk/public_html/wp-content/themes/bp-social/_inc/ajax.php:17) in /home/antitalk/public_html/wp-content/plugins/buddypress/bp-themes/bp-default/_inc/ajax.php on line 81