The German Sharp S or Eszett does not have an uppercase equivalent. Instead when ‘ß’ is converted to ‘SS’. The conversion of ‘ß’ to ‘SS’ requires a special rule, and increases the length of a word, thus disallowing inplace case conversion. Furthermore, my general rule of converting all words to lowercase before looking them up in the dictionary won’t work because the conversion of ‘SS’ to lowercase is ambiguous; it can be ‘ss’ or ‘ß’. I do plan on dealing with this eventually.