OSX Lion has wcscasecmp, but is not GNU

--- configure.in
+++ configure.in
@@ -67,6 +67,7 @@
 dnl Checks for library functions.
 AC_CHECK_FUNCS(strstr)
 AC_CHECK_FUNCS(strcasecmp)
+AC_CHECK_FUNCS(wcscasecmp)
 
 dnl create testsuite
 dnl AC_CONFIG_TESTDIR([tests])
--- src/html.c
+++ src/html.c
@@ -40,7 +40,7 @@
 	link_inline[DEF_STR_LEN]; /* Link of a HTML-Tag */
 
 /* ------------------------------------------------ */
-#if defined(MULTIBYTE) && ! defined(__GNU_LIBRARY__)
+#if defined(MULTIBYTE) && ! defined(HAVE_WCSCASECMP)
 #include <wchar.h>
 static int wcscasecmp(const wchar_t *s1, const wchar_t *s2)
 {