Missing "--parent-mirror-binary-updates" for live-build 4.x?

[Steven Shiau <steven@nchc.org.tw>]

Dear all,
In the manual of live-build 4.0.4-1, option
"--parent-mirror-binary-updates" is shown:
$ man -P cat lb_config | grep -- --parent-mirror-binary-updates
            [--parent-mirror-binary-updates URL]
       --parent-mirror-binary-updates URL

However, when I ran "lb config" with this option, it gave me an error:
$ lb config --parent-mirror-binary-updates http://ftp.debian.org/
[2015-01-24 21:12:03] lb config --parent-mirror-binary-updates
http://ftp.debian.org/
lb config: unrecognized option '--parent-mirror-binary-updates'

This option does exist in live-build 3.x.
So is this option no more in live-build 4.x or is the manual wrong?
Thanks.

Steven.

-- 
Steven Shiau <steven _at_ stevenshiau org>
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