There is a new feature here - spelling checker - located as a button underneath the new thread, new reply and edit post pages. When you click on it, a new window opens - you will need to manually cut and paste the text you want to check into the box, check the spelling, and cut and paste back. Unfortunately, there is no other way of doing it without using up too much server space and resouces.
Added to the PM system too!
Enjoy!

Added to the PM system too!
Enjoy!