You might consider this sort of thing out of scope,
but I knocked up an Ajax based spell checker using
Jazzy and and it's all yours if you want it.
It works by wrapping the existing event API with a
servlet. All the javascript required to perform
spell checks is included in the jazzy.js file.
I wasn't sure how (or if) you would want to structure
the ajax stuff, so I bundled it all in a seperate
file instead of a traditional patch.
A online demo of the ajax spell checker is located
at...
http://www.saintdiego.com/saint-diego/saint-
diego/jazzyDemo.do
The README file included with the patch has more
details.
Please contact me with any suggestions or comments.
Ajax Spell Checker Patch