When str_split was given an empty string it returned one empty char instead of false - that annoyed strpbrk wich wanted at least one char in $char_list

git-svn-id: svn://oss.beweb.dbc.dk/sync_php/php/OpenLibrary/class_lib/trunk@73115 30e9dc4a-7611-4fbc-83ba-eecf79b76bd0