# %header will be in random order
my $q = CGI->new;
my %header = map { lc($_) => $q->http($_) } $q->http;

# %ENV is in random order
print Dumper \%ENV

my $h = HTTP::Headers->new(%ENV);

# this returns the headers in the recommended 
# "Good Practice" order. 
print Dumper $h->header_field_names;

# this doesn't work as well
print $h->as_string;