The new version 2.0 of the (Mozilla) Firefox web browser supports spell checking in web forms. This is a new feature with some obvious deficiencies that might be improved in coming versions.
Has there been any discussion, proposal or attempts to adopt Firefox' spell checker to Wikipedia's needs? Currently, wiki syntax is not recognized, and the language needs to be set manually. If I go to nl.wikipedia.org and click edit, I want the browser to automatically select the Dutch spelling dictionary. And there is no need to apply spell checking to interwiki links, external URLs, template names or template parameter names. Perhaps the website needs to communicate this to the browser by some tags to the HTML, e.g. <textarea lang=nl syntax=mediawiki>?
Currently the language support in Firefox is only a spell checker. As a comparison, OpenOffice also offers automatic corrections (if I type "abotu", this can automatically be corrected to "about"), hyphenation, and a thesaurus. I have no idea what is planned, but I guess these features will eventually creep into Firefox too.
One option offered by the interaction between browser and website is that the spelling dictionary could be maintained and updated online. For example, if I spell "abotu", a word not found in the browser's built-in dictionary, the browser could send a request to Wiktionary (-Z) for advice on that word. This option is not so obvious to developers of OpenOffice as it should be to developers of Firefox. This opens up a new can of legal worms: Should Wiktionary offer spelling help only for documents that are released under a free license?