I'm reviving this old thread.  As my work on the glibc patches
is over and I'm going to apply them on Monday  I'd like to hear
your final opinion about importing the locale data for your languages.
Please note that there will be no visible changes in the locales
if the locale data are not changed. So far I have only one 100% positive
opinion from the Polish translator (thank you Piotr) and some attention
from Greek,  Serbian,  and Scottish Gaelic  translators.
Here is the list of languages from which I'd like to hear the opinion
whether to update the locale data now:
Armenian, Asturian, Belarusian, Catalan, Croatian, Czech, Farsi,
Finnish, Greek, Kashubian, Lithuanian, Ossetian, Russian, Scottish Gaelic,
Silesian, Slovak, Sorbian (Upper and Lower), Ukrainian, Walloon.
For those languages which are updated the currently used "%B" and
"%b" format specifiers will automatically start displaying the
genitive case which is usually correct. There are however some
applications (e.g., calendars) which need the nominative case.
In those applications the developers and translators would have
to change it to "%OB" and "%Ob", respectively.
In case of Finnish the answer is probably "no" because their
system of generating the genitive case is simple and they have already
In case of Czech, Serbian and (probably) Slovak the case is controversial.
As far as I was told, in those languages the nominative case is used
normally in dates unless whole date is in a genitive case. However,
the Serbian translator suggested that this would be still useful
for their language even if this would cause changing almost all "%B"
format specifiers to "%OB".  Alternatively, those languages may
decide not to use this new feature.
In case of Asturian, Catalan, and Walloon: the genitive case is
created adding "de" before the month name which is changed to "d’"
if the month name starts with a vowel (e.g., "d’abril" in Catalan).
In those languages "de" would have to be removed from all format
specifiers because the correct "de"/"d’" prefix would be already
contained in "%B" format specifier.
In all other languages the change seems to be obviously correct
and expected but, again, I don't want to change anything without
asking the language communities about their opinion.
Also, CLDR suggests that the languages which do not need the
nominative/genitive case can use this feature to display the month
name capitalized when it is standalone (e.g., "Enero" in Spanish)
and lowercase when it is used in a full date (e.g., "20 de enero").
CLDR provides the different lowercase/uppercase month names for
Albanian, Azerbaijani, Bosnian, Chechen, Galician, Italian, Kazakh,
Kyrgyz, Spanish (only Peru and Uruguay, I really don't understand why),
Note that these lists may be incomplete.
Please find and review my proposed changes in my github repo. 
I'm sorry for this kinda off-topic post because this is not directly
about GNOME but I was told that this list is the best place to find
a diverse community of translators. Also note that glibc is the base
library for almost all Linux software, definitely including GNOME.
See also the related glib2 bug . Let's hope that the next release
of GNOME Shell and GNOME Calendar will display the dates correctly
in every language.
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