Could be, the idea was once a cipher is forced it either works or you get some other error pointing to the real problem.
However you need to translate that cipher value into what nginx configuration understands;
See also
https://blog.qualys.com/ssllabs/2013/08/05/configuring-apache-nginx-and-openssl-for-forward-secrecy
http://security.stackexchange.com/questions/87326/what-is-the-impact-of-removing-tls-rsa-with-rc4-128-sha-from-my-servers-cipher
However you need to translate that cipher value into what nginx configuration understands;
See also
https://blog.qualys.com/ssllabs/2013/08/05/configuring-apache-nginx-and-openssl-for-forward-secrecy
http://security.stackexchange.com/questions/87326/what-is-the-impact-of-removing-tls-rsa-with-rc4-128-sha-from-my-servers-cipher