Like tye said, use a tool to do this, and a good alternative to CGI.pm is HTML::Template. The <tmpl_var> tag has an option attribute named escape that, when set to html, will solve this problem in a very painless way for the coder. Here is a complete CGI script to demonstrate: 
#!/usr/bin/perl -T

use strict;
use warnings;
use CGI qw(header param);
use HTML::Template;

my $tmpl = HTML::Template->new(filehandle => \*DATA);
$tmpl->param(html => param('html'));
print header, $tmpl->output;

__DATA__
<html>
<head>
<title>textarea test</title>
</head>
<body>

<form>
<textarea name="html"><tmpl_var name="html" escape="html"></textarea>
<input type="submit" />
</form>

<hr />
<p><tmpl_var name="html"></p>

</body>
</html>

[download]
Be sure and view the source and inspect the contents of the textarea element.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: HTML Problem getting entities into a textarea by jeffa
in thread HTML Problem getting entities into a textarea by muad33b

Title:
Use:  <p> text here (a paragraph) </p>
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