-/* Then the character class tables. Don't try to be clever and save effort
-on exclusive ones - in some locales things may be different. Note that the
-table for "space" includes everything "isspace" gives, including VT in the
-default locale. This makes it work for the POSIX class [:space:]. */
+/* Then the character class tables. Don't try to be clever and save effort on
+exclusive ones - in some locales things may be different. Note that the table
+for "space" includes everything "isspace" gives, including VT in the default
+locale. This makes it work for the POSIX class [:space:]. Note also that it is
+possible for a character to be alnum or alpha without being lower or upper,
+such as "male and female ordinals" (\xAA and \xBA) in the fr_FR locale (at
+least under Debian Linux's locales as of 12/2005). So we must test for alnum
+specially. */