The javascript file for the editor part, which covers all buttons in the editor is 'ckeditor.js', this is hosted on the web server under my control (so not linking to another website where I don't have control of updates) this file hasn't changed. Something is amiss somewhere. I will try some thing tommorow, may be its calling a function from a file which dosn't exist. When Ray tried it, its the first time his iPad has been on the website, I wonder if its something caught in the cache on the iPad, but probably not, just plucking ideas.
Anyway, I'll try something tomorrow as gotta progress on another website tonight.