d-i preseed not effective on network install

[Your Mom]

Network install via PXE boot. A preseed.cfg file on the initrd.gz with the following lines is not effective. Despite the configuration, the installer inquires for a locale, since language and country do not combine to a known locale. After locale selection, d-i inquired for keymap.

preseed.cfg excerpt:
d-i debian-installer/language string en
d-i debian-installer/country string DE
d-i debian-installer/locale string en_US.UTF-8
d-i console-setup/ask_detect boolean false
d-i keyboard-configuration/xkb-keymap select us
...

[Your Mom (h-blut)]

Places the following bug in a different context. Newer version ( 16.04 )
https://bugs.launchpad.net/ubuntu/+source/installation-guide/+bug/669453