No cipher parameter in mysql_ssl_set

The mysql_ssl_set function in libmariadb does not have a cipher parameter. This differs from the mysql c api.

From libmariadb - mysql.h:
int STDCALL mysql_ssl_set(MYSQL *mysql, const char *key,
const char *cert, const char *ca,
const char *capath);

From MySQL 5.5 documentation (http://dev.mysql.com/doc/refman/5.5/en/mysql-ssl-set.html):
my_bool mysql_ssl_set(MYSQL *mysql, const char *key, const char *cert, const char *ca, const char *capath, const char *cipher)

My understanding is that the API is supposed to be the same.