As a complement to my previous I should mention that one should generally the encodeURIComponent() function for escaping the content one wishes to send. So instead of esacping the "&" or anything like it one can simply escape the whole content like: content = encodeURIComponent( content );
just a quick note.. that's done behind the scenes when you use Element.serialize (or Form.serialize) in prototype.js, and it's the method that is automatically called when you use the rails remote methods defined in the helpers.
the only thing you should be careful about is encodeURIComponent by design will always send the data in UTF-8, whatever the encoding of your original page was, so take it into account server side or you'll end up with strange characters.
regards,
javier ramirez