if you use icefaces, they have a tag inputRichText that is FCK editor wrapped in a JSF control.  Richfaces has it coming in 3.3 (whenever that comes out...)

Not sure if you're still looking, but you can in fact embed tiny mce in the current iterations of richfaces, by doing something like this:

Javascript:
<script stype="text/javascript" src="/tiny_mce/tiny_mce.js"></script>
<script type="text/javascript">
tinyMCE.init({
     mode : "textareas",
     theme : "advanced",
     editor_selector : "mceAdvanced"
});
</script>

Control definition:
<h:inputTextarea id="bodyText" value="#{post.bodyText}" class="mceAdvanced" required="true" width="100%" />

I was surprised it worked so easily.