-dnl defines HAVE_WCSTR_H
-AC_CHECK_HEADERS(wcstr.h)
-dnl defined HAVE_WCTYPE_H
-AC_CHECK_HEADERS(wctype.h)
+
+dnl maybe wchar_t is in wcstr.h if we don't have wchar.h?
+if test "$ac_cv_header_wchar_h" != "yes"; then
+ dnl defines HAVE_WCSTR_H
+ AC_CHECK_HEADERS(wcstr.h)
+fi
+
+dnl checking for wctype.h is useless as we need wcslen(), not just wchar_t and
+dnl this function is never provided by it
+dnl AC_CHECK_HEADERS(wctype.h)
+