1. perl built on different OSes has different logic for @INC population.
2. Your script will work just fine if you'll place at the very start of it:

   BEGIN {
     @INC = ('/dir1','/your/special/dir/here');
   }
   # rest of your code goes here
   [download]

   I use that approach sometimes in my scripts.
3. recompiling perl is much easier that it initially seemes to. And lot of platform-specific READMEs help a lot.

addition: BTW what is your OS?

Courage, the Cowardly Dog
things, I do for love to perl...