You might notice a difference when using spell check in Outlook. Outlook uses the Mac OS X spell checker because of its Cocoa underpinnings. The rest of Office is still Carbon-based and uses the dictionaries supplied by Office.
A user asked the following question on the Mactopia forums:
Why in the Finnish language version of Office 2011 there is no Finnish spell check in Outlook although the language of the program is Finnish . . .
Continue Reading: Spell check differs in Outlook