I think you need to alter your submitted content to allow for that.
if using PHP try http://php.net/htmlentities with ENT_QUOTES
what that will do will convert your html into safe to use chars/quotes
ie, this markup
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Untitled Document</title>
</head>
<body>
<p>hello world</p>
</body>
</html>
Would become this markup.
<p><!DOCTYPE HTML><br /><html><br /><head><br /><meta http-equiv="Content-Type" content="text/html; charset=utf-8"><br /><title>Untitled Document</title><br /></head><br /><br /><body><br /><p>hello world</p><br /><br /></body><br /></html></p>