印刷するときにも引用を線で表示するにはどうすればよいですか?

印刷用テンプレートで引用を<blockquote>に変換して、CSSで左側に線を入れると引用を線で表示して印刷できます。たとえば以下のテンプレートをprint.templateとして保存するとそれらしくなります。

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>

<head>
	<title>{@HtmlEscape(@Subject())}</title>
	<style type="text/css">
	body {{ margin-left: 3em; margin-right: 3em; }}
	.header-title {{ font-weight: bold; font-size: 90%; }}
	.header-value {{ font-size: 90%; }}
	.body {{ font-family: monospace; }}
	blockquote {{
		border-width: 0px 0px 0px 2px;
		border-color: blue;
		border-style:solid;
		padding-left:1em;
		margin-left: 0.5em;
	}}
	</style>
</head>

<body>
	<table border="0" cellspacing="0" cellpadding="0">
		<tr>
			<td colspan="2"><hr size="3" style="color: lightblue"></td>
		</tr>
		<tr style="padding-bottom: 5px;">
			<td width="70" nowrap class="header-title">To: </td>
			<td width="100%" class="header-value">{@HtmlEscape(@FormatAddress(To))}</td>
		</tr>
		{@If(Cc, @Concat('
		<tr style="padding-bottom: 5px;">
			<td width="70" nowrap class="header-title">Cc: </td>
			<td width="100%" class="header-value">',
			@HtmlEscape(@FormatAddress(Cc)),
			'</td>
		</tr>'), '')}
		<tr style="padding-bottom: 5px;">
			<td width="70" nowrap class="header-title">From: </td>
			<td width="100%" class="header-value">{@HtmlEscape(@FormatAddress(From))}</td>
		</tr>
		<tr style="padding-bottom: 5px;">
			<td width="70" nowrap class="header-title">Date: </td>
			<td width="100%" class="header-value">{@FormatDate(@Date(Date), '%D %M1 %Y4 %h:%m:%s %z')}</td>
		</tr>
		<tr>
			<td width="70" nowrap class="header-title">Subject: </td>
			<td width="100%" class="header-value">{@HtmlEscape(@Subject())}</td>
		</tr>
		<tr>
			<td colspan="2"><hr size="3" style="color: lightblue"></td>
		</tr>
		<tr>
			<td colspan="2" class="body"><p>{-@Script(<<END
function getQuoteDepth(s) {
	var depth = 0;
	var n = 0;
	for (n = 0; n < s.length; ++n) {
		var c = s.charAt(n);
		if (c == '>')
			++depth;
		else if (c == ' ' || c == '\t')
			;
		else
			break;
	}
	return { "index": n, "depth": depth };
}

function escape(s) {
	return s.replace(/&/g, "&amp;").replace(/</g, "&lt;");
}

var body = "";
var lines = arguments(0).split("\n");
var quote = 0;
for (var n = 0; n < lines.length; ++n) {
	var line = lines[n];
	var qd = getQuoteDepth(line);
	var q = qd.depth;

	if (q > quote) {
		for (var m = 0; m < q - quote; ++m)
			body += "<blockquote>";
	}
	else if (q < quote) {
		for (var m = 0; m < quote - q; ++m)
			body += "</blockquote>";
	}
	quote = q;
	body += escape(line.substring(qd.index));
	body += "<br>";
}
result.value = body;
END
, 'JScript', @Body('', :BODY-RFC822INLINE))-}</p></td>
		</tr>
	</table>
</body>

</html>