Innately SITEFORUM provides different editors which you can switch if required. By default you work with the FCK editor, but the following other WYSIWYG editors are available:
To change the WYSIWYG editor pleaso go to "Tools & Administration > Design & Layout > General Preferences". In the upper area CMS, Shop-System WYSIWYG HTML Editor
you can change to another editor by using the selection box. Don't forget to save the settings.