Outlook 2007 - Problem with Greek fonts

I have a problem with Greek characters in the Outlook 2007. When I type the subject at an e-mail then no problem. But when I type in the body of the e-mail message either keyboard doesn't function or types 1-2 Greek characters and stops! Any idea to solve it? (As far as I know the MS Word-2007 editor is build-in into Outlook 2007). - OS: Windows Vista - MS Office 2007 - Manufacturer/Model: Toshiba Satellite A300