all such info should be get at tinyMCE doc resources.. we do not changet the client side widget anyhow. Just wrapped as the JSF component.
The TinyMCE demo has a control to "Select text color" but that control is not visible in rich:editor, even in advanced mode. Is it possible to make it visible?
The "Select Text Color" button seems to be related to theme options e.g.
theme_advanced_buttons2 : "cut,copy,paste,|,forecolor,backcolor",
The TinyMCE demo I looked at and the above code are here: http://tinymce.moxiecode.com/examples/full.php
all tinyMCE parameters are avilable to be defined using f:param or config file. please read the documentation carefully and download demo source to check how its done. (link in my signature)