Upgrading Perl on Cobalt gear is always a nuisance, since the built-in LCD modules rely on a few other modules being present.
After installing Perl 5.8.5 in the usual way (getting the latest tar.gz, unpacking, sh Configure && make && make test && make install, etc.), I had to go into CPAN to get the following:
# perl -MCPAN -e shell ... cpan> install Locale::gettext ... cpan> install Jcode::Unicode
Note: I did the right thing(TM) and prefixed the install to /usr, and not /usr/local, which automatically set @INC to load most of the pre-existing stuff.
So far, it's working fine.