4c1a35e34c
It seems that \s includes non-breaking space, and the typical one-byte representation of that is the same as some parts of multibyte unicode characters. Therefore, you need to include the u modifer on the regular expressions. Also, remove any number of <br /> at the end of the answer. Thanks to Joseph Rézeau and Jean-Michel Vedrine for working out what the problem was, and how to fix it.