# mtproto-proxy -6 --address 2001:41d0:1:8b3b::1 ...
[17522][2018-06-07 09:53:41.565916 local] Invoking engine mtproxy-0.01 compiled at Jun 6 2018 19:37:18 by gcc 4.9.2 64-bit after commit 580909cbca12a2f8529dbb387edf8e9bc5bd4e3a
[17522][2018-06-07 09:53:41.566182 local] Can not convert '2001:41d0:1:8b3b::1' to ip addr: Success
# mtproto-proxy -6 --address '[2001:41d0:1:8b3b::1]' ...
[17527][2018-06-07 09:54:08.385768 local] Invoking engine mtproxy-0.01 compiled at Jun 6 2018 19:37:18 by gcc 4.9.2 64-bit after commit 580909cbca12a2f8529dbb387edf8e9bc5bd4e3a
[17527][2018-06-07 09:54:08.386029 local] Can not convert '[2001:41d0:1:8b3b::1]' to ip addr: Success