Sounds like the here document in the original Korn script was interpolating variables - I don't know ksh, but in bash you can stop it from doing that like so:

#!/bin/bash

cat <<END
foo <$HOME>
END
cat <<'END'
bar <$HOME>
END

### Output:
# foo </home/foobar>
# bar <$HOME>
[download]

That happens to be the equivalent behavior as Perl in regards to stopping interpolation in here documents. If you can, I'd strongly suggest always giving your scripts to perl this way - as LanX said, trying to get values into Perl via interpolation is going to end up being a pain, so use @ARGV (that would be my suggestion) or %ENV.