#!/usr/bin/perl
use strict;
use warnings;

my %env;
BEGIN {
  %env = (
      perlmodule_eigen        => [
          "/arbeit/perlmodule/",
          "/arbeit/perlmodule/lib/perl/5.10.0"
        ],
    );
}
use lib @{$env{perlmodule_eigen}};

# ...