ctype second opinions

Dear all, I would like your opinion, please. I'm currently arguing a bug in the PHP database, http://bugs.php.net/bug.php?id=18428, and basically feel that I have made the correct choice, while the PHP developer feels otherwise. The ctype functions in PHP currently return TRUE on an empty string. For instance, ctype_alpha('a') == TRUE, ctype_alpha('1') == FALSE, ctype_alpha('') == TRUE. I argued that since no characters in an empty string match the criteria, an empty string should return FALSE. The developer argued that "in an empty string every of the 0 charactetrs matches the (criteria)", so it should return TRUE. I guess this is all semantics, but it also means that my lexer in DBA (DBA/Sql_lex.php) has to use if (strlen($c) && ctype_alpha($c)) everytime it uses a ctype function, since end-of-input can be reached at any time. I've included compatibility versions of the ctype functions in DBA/ctype.php since ctype is a relatively new extension and not included by default until PHP 4.2, but they return false on an empty string (they actually operate on a single character, like the real ctype functions). What should I do? Do I have a case or should I concede? - Brent