Spellcheck problem

We have confirmed that this is a bug related to the "display web pages in this language"-setting in your browser. If you set that to english, german, spanish, french or japanese it works but if you select swedish, finnish, danish, hindu, esperanto or some other language it does not work. It is also isolated to Word, Powerpoint spellcheck works. You can have the display language in english and still have spell check in another language.

It is not related to any third party product.
It is confirmed by Microsoft and sent as a bug to the product team.