Cannot activate plugin

The ultimate Facebook-plugin will not activate due to ‘fatal error’:

Fatal error: Uncaught exception ‘Exception’ with message ‘Facebook needs the CURL PHP extension.’ in /home/vds/public_html/clients/client2/web16/web/wp-content/plugins/wpmu-dev-facebook/lib/external/base_facebook.php:19 Stack trace: #0 /home/vds/public_html/clients/client2/web16/web/wp-content/plugins/wpmu-dev-facebook/lib/external/facebook.php(18): require_once() #1 /home/vds/public_html/clients/client2/web16/web/wp-content/plugins/wpmu-dev-facebook/wpmu-dev-facebook.php(102): require_once(‘/home/vds/publi…’:wink: #2 /home/vds/public_html/clients/client2/web16/web/wp-admin/plugins.php(142): include(‘/home/vds/publi…’:wink: #3 /home/vds/public_html/clients/client2/web16/web/wp-admin/plugins.php(144): plugin_sandbox_scrape(‘wpmu-dev-facebo…’:wink: #4 {main} thrown in /home/vds/public_html/clients/client2/web16/web/wp-content/plugins/wpmu-dev-facebook/lib/external/base_facebook.php on line 19

How do I fix this?