I've got the cvs downloaded (the last tarball is several years old), and I ran checkconfig.pl until I got no more warnings or errors:
root@public# $LJHOME/bin/checkconfig.pl [Checking for Perl Modules....]
[Checking LJ Environment...]
Great! But when I tried to fire up apache, the PerlRequire for $LJHOME/cgi-bin/modperl.pl syslogs [error] Can't locate Apache.pm in @INC and apache doesn't start. At this point, I'm stumped. I tried /usr/bin/perl -MCPAN -e 'install "Apache"' but it failed to installed Apache because it appears that it requires a version 1 mod_perl instead of a version 2 mod_perl. So at this point I actually look at the requirements page (I had foolishly assumed it needed current versions of perl and apache). I see that LJ specifically says that it does not run on Apache 2.
So I could roll back our webserver to 1972 (or whenever it was that apache 1 become obsolete) and put Apache 1 on it, or I could try to force LJ to work with Apache 2. Forcing it sounds painful to do on my own. Better to ask if someone has done this, or if I should give up and seek out some other blogging software? My hope/guess is that apache could be made to run (slowly) by skipping mod_perl and changing the various use and requires from Apache to Apache::compat. But that is only a guess. Does anyone know?