However, Microsoft hasn't implemented the usual features you'd expect to find in a good spellchecker. You have the ability to enable or disable the highlighting of misspelt words and autocorrect. You also have the ability to provide your own list of words to exclude, include and autocorrect. If you check the spellchecking options for Microsoft Word you'll find a whole range of other options.
I provide files for Internet Explorer which provides the preferred Australian English spelling. The word 'mom', which is normally included in the dictionary, is then marked as a spelling error. The problem however is the spellcheck does not appear to check capitalised words. The word 'MOM' for example does not appear as a spelling error and that isn't correct for Australia.
Hopefully Microsoft will correct this oversight in the future.