Description:
------------
Test on FC3, FC6 ( RedHat Fedora)
On FC3, PHP version is 4.3.11
On FC6, PHP version is 5.1.6

    $strary = split("[@#^!]", $password);  <== 
                                              if $password = aaaaa@ , $num =2 <= incorrectly on FC3 , FC6 (Fedora)
                                              if $password = @aaaaa , $num =2 <= incorrectly on FC3 , FC6 (Fedora)

                                              if $password = a@a@a , $num=3 <= correctly
                                              if $password = a@a ,   $num=2 <= correctly
    $num = count($strary);

    $s="";  // debug
    if (!(ctype_alnum($s))) echo "false<br>";  // debug
    echo "num = " . $num . "<BR>";  // debug  

    for ($ii = 0; $ii < $num; $ii++)
    {
       echo "strary[ii] = " . $strary[$ii] . "<BR>";  // debug
          if (!(ctype_alnum($strary[$ii])))
            {
              return "Password must contain?w@ # ^ !?x";//"a password should contain only alphanumeric characters and @ # ^ !";
            }
    }