There is a feature in ITBM that will allow you to have spell checker enabled on string attributes.
You set this in Object Designer by highlighting the attribute you wish to have it on, for example "Description" and then in Properties you set "As You Spell Check" to TRUE.
You can add words to this by right clicking on a misspelt (or not recognised) word and choose to "Add".
If you however want to add in more than one word at a time, you can do so directly in the dictionary.
To do this, open path: (default ootb path)
C:\Program Files\LANDesk\LANDesk ServiceDesk
Open file: "AddedWords.dict" up in Notepad.
Then simply type in the words you want to add with a 'return' in between every word and save the file. For example:
Restart your Console for the change to take affect.
Please note that If this is done on a local machine it will only take affect on that machine.