IPv6 fails for set_real_ip_from in 1.2.1

I noticed in the 1.2.1 changelog that set_real_ip_from is supposed to
support IPv6 addresses. Unfortunaly I get a configuration error when I
try it.

This works fine:
set_real_ip_from 127.0.0.1;
real_ip_header X-Forwarded-For;

This fails:
set_real_ip_from 127.0.0.1;
set_real_ip_from ::1;
real_ip_header X-Forwarded-For;

$ nginx -t
nginx: [emerg] invalid parameter “::1” in nginx.conf:22
nginx: configuration file nginx.conf test failed

Posted at Nginx Forum:

On Mon, Jun 11, 2012 at 08:59:38AM -0400, dakrer wrote:

set_real_ip_from ::1;
real_ip_header X-Forwarded-For;

$ nginx -t
nginx: [emerg] invalid parameter “::1” in nginx.conf:22
nginx: configuration file nginx.conf test failed

For IPv6 to work, nginx should be built with --with-ipv6.