Certo.

x.html
codice:
<form method="post" action="y.asp">
<textarea name="testo" cols="10" rows="10"></textarea> <input type="submit" value="INVIA" />
</form>
y.asp
codice:
<%
testo = request.form("testo")
testo = server.HTMLEncode(testo)
%>
<form>
<textarea name="testo" cols="10" rows="10"><%=testo%></textarea>
</form>