ereg_replace help wanted

Hi, I don't want to spend a lot of time leaning how to use this function but I have a problem that I think it can solve. I have a web form that allows the user to (amongst other things) submit a pagerange to my database. Using '-' and ',' as separators, I am able to calculate the number of pages being submitted. I can handle roman or arabic numerals and a typical range might look like: 'ix-xxvii,21-30,64' and that would usually give me a page count of 30. The problem is that I think that some of my users are pasting the range in, rather than re-typing (I don't really want to stop them from pasting) and I am sure that sometimes the '-' is coming over as something other than a conventional hyphen. Can anyone suggest a filter that will handle my hyphens correctly, regardless of what type of hyphen the user is entering? MTIA George in Oxford