in reply to Perl In, Perl Out...

I like to install a perl that is in a completely different directory than the system perl. I have a script that unpacks the perl distribution, runs configure, and installs the modules such as DBD. I have to be very careful when the script installs the modules that the step
perl Makefile.PL
runs the correct perl, so I just give it the full path:
/home/username/perl5/bin/perl Makefile.PL
Also, I am careful to use separate directory trees for the perl build and the perl installation. So I compile perl in /home/username/perl5_build. I compile the modules in /home/username/perl5_build/modules.

I developed this methodology to make my perl builds reproducible and not depend on ppm working properly. I like ppm but I have seen it get confused and trash things too many times. Building everything from source is tedious but I have found it to be worthwhile and rewarding.

Other advantages of this approach are :

It should work perfectly the first time! - toma