G'day swampyankee,

I'm also running Mac OS X 10.7.5 and had no problem installing from CPAN: 

$ cpan

cpan shell -- CPAN exploration and modules installation (v1.9800)
Enter 'h' for help.

cpan[1]> install Chart::Gnuplot

[download]
Reading '/Users/ken/.cpan/Metadata'
  Database was generated on Thu, 20 Sep 2012 02:31:03 GMT
Fetching with LWP:
http://mirror.as24220.net/pub/cpan/authors/01mailrc.txt.gz
Reading '/Users/ken/.cpan/sources/authors/01mailrc.txt.gz'
......................................................................
+......DONE
Fetching with LWP:
http://mirror.as24220.net/pub/cpan/modules/02packages.details.txt.gz
Reading '/Users/ken/.cpan/sources/modules/02packages.details.txt.gz'
  Database was generated on Sun, 23 Sep 2012 05:07:03 GMT
......................................................................
+......DONE
Fetching with LWP:
http://mirror.as24220.net/pub/cpan/modules/03modlist.data.gz
Reading '/Users/ken/.cpan/sources/modules/03modlist.data.gz'
......................................................................
+......DONE
Writing /Users/ken/.cpan/Metadata
Running install for module 'Chart::Gnuplot'
Running make for K/KW/KWMAK/Chart/Gnuplot/Chart-Gnuplot-0.17.tar.gz
Fetching with LWP:
http://mirror.as24220.net/pub/cpan/authors/id/K/KW/KWMAK/Chart/Gnuplot
+/Chart-Gnuplot-0.17.tar.gz
Fetching with LWP:
http://mirror.as24220.net/pub/cpan/authors/id/K/KW/KWMAK/Chart/Gnuplot
+/CHECKSUMS
Checksum for /Users/ken/.cpan/sources/authors/id/K/KW/KWMAK/Chart/Gnup
+lot/Chart-Gnuplot-0.17.tar.gz ok
Scanning cache /Users/ken/.cpan/build for sizes
......................................................................
+......DONE

  CPAN.pm: Building K/KW/KWMAK/Chart/Gnuplot/Chart-Gnuplot-0.17.tar.gz

Checking if your kit is complete...
Looks good
Writing Makefile for Chart::Gnuplot
Writing MYMETA.yml and MYMETA.json
cp lib/Chart/Gnuplot/Util.pm blib/lib/Chart/Gnuplot/Util.pm
cp lib/Chart/Gnuplot.pm blib/lib/Chart/Gnuplot.pm
Manifying blib/man3/Chart::Gnuplot.3
  KWMAK/Chart/Gnuplot/Chart-Gnuplot-0.17.tar.gz
  /usr/bin/make -- OK
Running make test
PERL_DL_NONLAZY=1 /Users/ken/perl5/perlbrew/perls/perl-5.14.2_WITH_THR
+EADS/bin/perl "-MExtUtils::Command::MM" "-e" "test_harness(0, 'blib/l
+ib', 'blib/arch')" t/*.t
t/axisLabel.t ... ok   
t/axisTics.t .... ok   
t/border.t ...... ok   
t/chartTitle.t .. ok   
t/copy.t ........ ok   
t/dataSrc.t ..... ok   
t/grid.t ........ ok   
t/legend.t ...... ok   
t/use.t ......... ok   
All tests successful.
Files=9, Tests=22,  1 wallclock secs ( 0.05 usr  0.02 sys +  0.53 cusr
+  0.08 csys =  0.68 CPU)
Result: PASS
  KWMAK/Chart/Gnuplot/Chart-Gnuplot-0.17.tar.gz
  /usr/bin/make test -- OK
Running make install
Installing /Users/ken/perl5/perlbrew/perls/perl-5.14.2_WITH_THREADS/li
+b/site_perl/5.14.2/Chart/Gnuplot.pm
Installing /Users/ken/perl5/perlbrew/perls/perl-5.14.2_WITH_THREADS/li
+b/site_perl/5.14.2/Chart/Gnuplot/Util.pm
Installing /Users/ken/perl5/perlbrew/perls/perl-5.14.2_WITH_THREADS/ma
+n/man3/Chart::Gnuplot.3
Appending installation info to /Users/ken/perl5/perlbrew/perls/perl-5.
+14.2_WITH_THREADS/lib/5.14.2/darwin-thread-multi-2level/perllocal.pod

[download]
  KWMAK/Chart/Gnuplot/Chart-Gnuplot-0.17.tar.gz
  /usr/bin/make install  -- OK

cpan[2]> q
Lockfile removed.

[download]

I'm using perlbrew with Perl 5.14.2.

You may already be aware of this but it's generally considered a bad idea to modify Mac OS X's system Perl. If you are doing this, that may have some bearing on your problem (I'm very much guessing here). Here's a discussion of this with some options: Are there any major Perl issues with Mac OS X Lion?

-- Ken

In reply to Re: Trying -- and failing -- to install modules from cpan by kcott
in thread Trying -- and failing -- to install modules from cpan by swampyankee

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