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.

@echo off
set PATH=C:\myperl\bin;%PATH%;
set HTTP_PROXY_USER=SECRETUSERNAME
set HTTP_PROXY_PASS=SECRETPASSWORD
set http_proxy="http://%HTTP_PROXY_USER%:%HTTP_PROXY_PASS%@firewall.wo
+rk.com:8080"
set https_proxy="http://%HTTP_PROXY_USER%:%HTTP_PROXY_PASS%@firewall.w
+ork.com:8080"
set ftp_proxy="http://%HTTP_PROXY_USER%:%HTTP_PROXY_PASS%@firewall.wor
+k.com:8080"

%1 %2 %3 %4 %5 %6 %7 %8 %9
[download]

Update the path variable to point to the directory holding the actual Perl executable you want to run.

HTH