Fatal error when trying to register new user. Cannot redeclare _recaptcha

pehja

I am getting this and can't se what the problem is.

Fatal error: Cannot redeclare _recaptcha_qsencode() (previously declared in /home/spinneti/public_html/wp-content/plugins/wp-recaptcha/recaptchalib.php:47) in /home/spinneti/public_html/vanilla/library/vendors/recaptcha/functions.recaptchalib.php on line 55