There is /usr/share/locale/lt_LT directory in glibc-2.1.3-21, but not in
Also Lithuanian locale should use iso-8859-13 charset, not iso-8859-4.
You're looking at wrong place. There is /usr/lib/locale/lt_LT
in glibc-2.2-5 and it uses iso-8859-13 locale.
/usr/share/locale/locale.alias even contains
(note that locale files (as opposed to message catalogues) are now
under /usr/lib, because they are endian dependent (thus cannot be
shared e.g. between small and big endian hosts).
The fact that there is no /usr/share/locale/lt_LT just means there
are no lithuanian message catalogues installed.