[kh99]

In the adminCP, go to Styles & Templates -> Style Manager, and choose "Edit Templates" from the dropdown next to your style (or Default Style if you have no custom styles), then expamd the section "Editor Templates".

You could also try creating a new style (The "Add New Style" link under the list of styles in the Style Manager) with no parent, and see if using that style fixes the problem. And you could try rebuilding the styles using Maintenance -> Update Counters -> Rebuild Styles (using the default options).