Day and month name localization uses wrong locale category

In 8.2, utils/adt/formatting.c uses our NLS mechanism to localize day and
month names (I assume for use by to_char). But since this necessarily ties
the outcome to the LC_MESSAGES setting, this comes out inconsistently with
Unix locale behavior, e.g.,

pei(at)bell:~$ locale
LANG=
LC_CTYPE="POSIX"
LC_NUMERIC="POSIX"
LC_TIME="POSIX"
LC_COLLATE="POSIX"
LC_MONETARY="POSIX"
LC_MESSAGES="POSIX"
LC_PAPER="POSIX"
LC_NAME="POSIX"
LC_ADDRESS="POSIX"
LC_TELEPHONE="POSIX"
LC_MEASUREMENT="POSIX"
LC_IDENTIFICATION="POSIX"
LC_ALL=

pei(at)bell:~$ date +%A
Friday

pei(at)bell:~$ LC_MESSAGES=de_DE(at)euro date +%A
Friday

pei(at)bell:~$ LC_TIME=de_DE(at)euro date +%A
Freitag

Is there no API to get the localized names from the C library so that LC_TIME
takes effect?

--
Peter Eisentraut
http://developer.postgresql.org/~petere/