Recreate the ktuss.pot file with:

  xgettext -L C -o ktsuss.pot src/re_su.c
  xgettext -L C -kgettext_noop -j -o ktsuss.pot src/errors.h

Create an initial .po file for your language using the ktsuss.pot file
(example for greek):
  msginit -o el.po -i ktsuss.pot
or use a tool like poedit for that task.

Merge an old .po file with strings from a newly generated ktsuss.pot
file:
  msgmerge -U el.po ktsuss.pot

Create a ktsuss.mo file for your language from the .po file with:
  msgfmt -o ktsuss.mo el.po
and copy it inside your system's /usr/share/locale/el/LC_MESSAGES/
