<textarea id="contenu" rows="10" cols="70">et voila
prout</textarea>
<input type="submit" name="ajouter" value="Test" />
<script type="text/javascript" src="wysiwyg.js"></script>
<script type="text/javascript">
//<![CDATA[
wysiwyg("contenu","ajouter");
// ]]>
</script>