Command line:

/expsys/local/perl5/bin/cpan Data::Dumper

Also tried:

/usr/bin/perl -MCPAN -e 'install Data::Dumper'

... but this fails with:

Can't locate object method "install" via package "Data::Dumper" (perhaps you for got to load "Data::Dumper"?) at -e line 1.

... although it has worked for other modules (besides Data::Dumper)

cpan> o conf
CPAN::Config options from /expsys/local/perl5/lib/5.6.1/CPAN/Config.pm
+:
    commit             Commit changes to disk
    defaults           Reload defaults from disk
    init               Interactive setting of all options

    build_cache        10
    build_dir          /home/exp/.cpan/build
    cache_metadata     1
    cpan_home          /home/exp/.cpan
    dontload_hash
    ftp                /usr/5bin/ftp
    ftp_proxy          co.proxy.xxxxx.com
    getcwd             cwd
    gzip               /expert/bin/gzip
    histfile           /home/exp/.cpan/histfile
    histsize           100
    http_proxy         co.proxy.xxxxx.com
    inactivity_timeout 0
    index_expire       1
    inhibit_startup_message 0
    keep_source_where  /home/exp/.cpan/sources
    lynx               /expert/bin/lynx
    make               /usr/local/bin/make
    make_arg
    make_install_arg   UNINST=1
    makepl_arg         PREFIX=/expsys/local/perl5
    ncftp
    ncftpget
    no_proxy
    pager              /usr/5bin/pg
    prerequisites_policy ask
    proxy_user
    scan_cache         atstart
    shell              /usr/bin/ksh
    tar                /usr/5bin/tar
    term_is_latin      1
    unzip              /expert/bin/unzip
    urllist
        ftp://ftp.cs.colorado.edu/pub/perl/CPAN/
        ftp://ftp.ibiblio.org/pub/languages/perl/CPAN
        http://www.perl.com/CPAN/
    wget               /expert/bin/wget


cpan>
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