Fatal Error after Social Theme Activation

When aia activate the Social theme i get this

Fatal error: Cannot redeclare bp_dtheme_ajax_querystring() (previously declared in /home/wwwoilm/public_html/wp-content/plugins/buddypress/bp-themes/bp-default/_inc/ajax.php:20) in /home/wwwoilm/public_html/wp-content/themes/bp-social/_inc/ajax.php on line 63

I have seen this problem in another thread adressed by disabling a compatable pluggin but i dont have than installed, in fact i only have buddypress.

Thanks in advance for any help.