$PREFIX/lib/perl5/5.8.2/some/long/module/name

##</code><code>##

$PREFIX/lib/some/long/module/name

##</code><code>##

# if PREFIX is set, set LIB too
foreach my $arg (@ARGV) {
        if ($arg =~ /^PREFIX=(.*)/) {
                push @ARGV, "LIB=$1/lib";
        }
}