we carefully tested rich:editor in RichFaces 4.2.1.Final on JBoss 7.1.1.Final which contains Mojarra 2.1.7 and everything seems to work fine.
Please double-check that you have <h:head> on your page or in your template.
console? I expect there will be some.
p.s. I've been plagued by the dreaded 'CKEDITOR instance already exists' js error which stops notifyMessages from
working so I'm using ckeditor directly now, works like a dream.