First, check to see if you already have mod_perl installed:
If you see something like this, congratulations! Skip to: mod_perl Server Configuration
Perl - Verify that you have Perl version 5.6.1 or greater. If not, install or update it.
threads - verify that you are not using 5005threads
If instead it comes back with
then you must rebuild Perl without threads enabled or with -Dusethreads. If you are using a threaded MPM, it should report
If it doesn't, you need to rebuild Perl with -Dusethreads. If you want to use threads.pm, you mus use Perl 5.8.1 or higher with ithreads enabled. Other Dependencies: If you use CGI.pm or Compress::Zlib in your mod_perl code you need at least the following versions: CGI.pm 3.11 Compress::Zlib 1.09 One way to ensure you have all the mod_perl dependencies to install Bundle::Apache2 from CPAN. CGI.pm
To install from source, check out:
Installing mod_perl from source
mod_perl Server Configuration
This is distribution and installation specific, so I'll given some general information.
For Debian squeeze:
Go to you apache2 sites-available directory, and add this - either to default, or to a specific site:
Then reload your Apache server (this is OS and distribution-specific):