Spell Checker Settings
This window allows you to control spell checking in chat and IMs.
Enable spell checker: Check this to turn on spell checking. When enabled, text you have typed, that is determined to be mispelled, will be shown with a squiggly red underline.
Additional dictionaries: Two columns showing additional dictionaries which are installed, alone with those which are active. If one is listed in the Available column, it is installed, but not active (ie, will not be used to check spelling). You can move entries from one column to the other using the left and right arrows between the columns.
You can obtain additional dictionaries here.