BTW, in this context it might be interesting to show how i went over this bridge (AKA "Install Perl with threads" or so) using perlbrew:

karls-mac-mini:~ karl$ perlbrew list
  perl-5.16.2
  perl-5.16.3
  perl-5.17.7
  perl-5.18.0
  perl-5.18.1
* perl-5.18.2

karls-mac-mini:~ karl$  perlbrew install --as perl-5.18.2threads -Duse
+threads perl-5.18.2
Installing /Users/karl/perl5/perlbrew/build/perl-5.18.2 into ~/perl5/p
+erlbrew/perls/perl-5.18.2threads

This could take a while. You can run the following command on another 
+shell to track the status:

  tail -f ~/perl5/perlbrew/build.perl-5.18.2.log

karls-mac-mini:~ karl$ perlbrew list
  perl-5.16.2
  perl-5.16.3
  perl-5.17.7
  perl-5.18.0
  perl-5.18.1
* perl-5.18.2
  perl-5.18.2threads
karls-mac-mini:~ karl$ perlbrew switch perl-5.18.2threads
karls-mac-mini:~ karl$ perlbrew list
  perl-5.16.2
  perl-5.16.3
  perl-5.17.7
  perl-5.18.0
  perl-5.18.1
  perl-5.18.2
* perl-5.18.2threads
karls-mac-mini:~ karl$ perl -Mthreads
^C
[download]

Seems to be pretty cool.

Regards, Karl