If you cannot control the environment on your machine, but you want your code to do something different, I suggest you use a batch file to launch your program. My connection at work is limited by the firewall. I use this batch file called fwrap.bat to run ppm to install modules. Just run "fwrap ppm" or "fwrap perl script.pl" and it will and it will setup your environment.
in reply to Installing v5.8.4
Update the path variable to point to the directory holding the actual Perl executable you want to run.
%1 %2 %3 %4 %5 %6 %7 %8 %9