CreationDate in PDF files' metadata

Greetings,

I document my software using DocBook5 in a Debian GNU/Linux box. When the PDF
files are generated, the CreationDate field gets filled-up using a new value at
each run. This is a problem in our Debian effort to have "reproducible builds"
[0] with the "forensic science" idea that the same code should produce the same
binaries bit-by-bit [1].

It seems that FOP is responsible for filling-in the CreationDate field. 

Are you aware of a method to direct FOP in some manner to fill-in that
CreationDate with a constant value?

Thank you for your kind attention,

Sincerely,
Filippo

0 https://tests.reproducible-builds.org/debian/rb-pkg/unstable/amd64/msxpertsuite.html
1 https://reproducible-builds.org/

-- 

⢀⣴⠾⠻⢶⣦⠀  Filippo Rusconi, PhD
⣾⠁⢠⠒⠀⣿⡁   Scientist at CNRS
⢿⡄⠘⠷⠚⠋⠀   Debian Developer
⠈⠳⣄⠀⠀⠀⠀  http://msxpertsuite.org
          http://www.debian.org

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