$eol = "\n" unless defined $eol;

    # The calculation of content might update the headers
    # so we need to do that first.
    my $content = $self->content;

    return join("", $self->{'_headers'}->as_string($eol),
		    $eol,
		    $content,
		    (@_ == 1 && length($content) &&
		     $content !~ /\n\z/) ? "\n" : "",
		);
}


sub dump
{
    my($self, %opt) = @_;
    my $content = $self->content;
    my $chopped = 0;
    if (!ref($content)) {
	my $maxlen = $opt{maxlength};
	$maxlen = 512 unless defined($maxlen);
	if ($maxlen && length($content) > $maxlen * 1.1 + 3) {
	    $chopped = length($content) - $maxlen;
	    $content = substr($content, 0, $maxlen) . "...";
	}

	$content =~ s/\\/\\\\/g;
	$content =~ s/\t/\\t/g;
	$content =~ s/\r/\\r/g;

	# no need for 3 digits in escape for these
	$content =~ s/([\0-\11\13-\037])(?!\d)/sprintf('\\%o',ord($1))/eg;

	$content =~ s/([\0-\11\13-\037\177-\377])/sprintf('\\x%02X',ord($1))/eg;
	$content =~ s/([^\12\040-\176])/sprintf('\\x{%X}',ord($1))/eg;

	# remaining whitespace
	$content =~ s/( +)\n/("\\40" x length($1)) . "\n"/eg;
	$content =~ s/(\n+)\n/("\\n" x length($1)) . "\n"/eg;
	$content =~ s/\n\z/\\n/;

	my $no_content = "(no content)";
	if ($content eq $no_content) {
	    # escape our $no_content marker
	    $content =~ s/^(.)/sprintf('\\x%02X',ord($1))/eg;
	}
	elsif ($content eq "") {
	    $content = "(no content)";
	}
    }

    my @dump;
    push(@dump, $opt{preheader}) if $opt{preheader};
    push(@dump, $self->{_headers}->as_string, $content);
    push(@dump, "(+ $chopped more bytes not shown)") if $chopped;

    my $dump = join("\n", @dump, "");
    $dump =~ s/^/$opt{prefix}/gm if $opt{prefix};

    print $dump unless defined wantarray;
    return $dump;
}


sub parts {
    my $self = shift;
    if (defined(wantarray) && (!exists $self->{_parts} || ref($self->{_content}) eq "SCALAR")) {
	$self->_parts;
    }
    my $old = $self->{_parts};
    if (@_) {
	my @parts = map { ref($_) eq 'ARRAY' ? @$_ : $_ } @_;
	my $ct = $self->content_type || "";
	if ($ct =~ m,^message/,) {
	    Carp::croak("Only one part allowed for $ct content")
		if @parts > 1;
	}
	elsif ($ct !~ m,^multipart/,) {
	    $self->remove_content_headers;
	    $self->content_type("multipart/mixed");
	}
	$self->{_parts} = \@parts;
	_stale_content($self);
    }
    return @$old if wantarray;
    return $old->[0];
}

sub add_part {
    my $self = shift;
    if (($self->content_type || "") !~ m,^multipart/,) {
	my $p = HTTP::Message->new($self->remove_content_headers,
				   $self->content(""));
	$self->content_type("multipart/mixed");
	$self->{_parts} = [];
        if ($p->headers->header_field_names || $p->content ne "") {
            push(@{$self->{_parts}}, $p);
        }