" redhat: 500 SSL negotiation failed" while using rhn-proxy on RHEL7

[gitblessk]

It's good if I don't use --rhn-proxy, but it get failed while using proxy.

and i'm sure that the proxy is good.

INFO: Your API version is supported
INFO: Authentication on 127.0.0.1 successful
ERROR: Couldn't log in to redhat: 500 SSL negotiation failed:

rpm -qa perl-Socket6 perl-IO-Socket-INET6 perl-Net-INET6Glue perl-Crypt-SSLeay

perl-Net-INET6Glue-0.5-3.el7.noarch
perl-Crypt-SSLeay-0.64-5.el7.x86_64
perl-Socket6-0.23-15.el7.x86_64
perl-IO-Socket-INET6-2.69-5.el7.noarch