--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2009-03-08  Bruno Haible  <bruno@clisp.org>
 
+	New module 'unicase/u8-is-cased'.
+	* lib/unicase/u8-is-cased.c: New file.
+	* lib/unicase/u-is-cased.h: New file.
+	* modules/unicase/u8-is-cased: New file.
+
 	Tests for module 'unicase/u32-is-casefolded'.
 	* modules/unicase/u32-is-casefolded-tests: New file.
 	* tests/unicase/test-u32-is-casefolded.c: New file.

new file mode 100644
--- /dev/null
+++ b/lib/unicase/u-is-cased.h
@@ -0,0 +1,128 @@
+/* Test whether case matters for a Unicode string.
+   Copyright (C) 2009 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2009.
+
+   This program is free software: you can redistribute it and/or modify it
+   under the terms of the GNU Lesser General Public License as published
+   by the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+int
+FUNC (const UNIT *s, size_t n, const char *iso639_language,
+      bool *resultp)
+{
+  UNIT normsbuf[2048 / sizeof (UNIT)];
+  UNIT *norms;
+  size_t norms_length;
+  UNIT mappedbuf[2048 / sizeof (UNIT)];
+  UNIT *mapped_toupper;
+  UNIT *mapped_tolower;
+  UNIT *mapped_totitle;
+  size_t mapped_length;
+
+  /* Apply canonical decomposition to S.  */
+  norms_length = sizeof (normsbuf) / sizeof (UNIT);
+  norms = U_NORMALIZE (UNINORM_NFD, s, n, normsbuf, &norms_length);
+  if (norms == NULL)
+    /* errno is set here.  */
+    return -1;
+
+  mapped_length = sizeof (mappedbuf) / sizeof (UNIT);
+
+  /* Apply toupper mapping.  */
+  mapped_toupper = U_TOUPPER (norms, norms_length, iso639_language, NULL,
+			      mappedbuf, &mapped_length);
+  if (mapped_toupper == NULL)
+    goto fail;
+
+  /* Compare.  */
+  if (!(mapped_length == norms_length
+	&& U_CMP (mapped_toupper, norms, norms_length) == 0))
+    {
+      if (mapped_toupper != mappedbuf)
+	free (mapped_toupper);
+      goto yes;
+    }
+
+  /* Apply tolower mapping.  */
+  mapped_tolower = U_TOLOWER (norms, norms_length, iso639_language, NULL,
+			      mapped_toupper, &mapped_length);
+  if (mapped_tolower == NULL)
+    {
+      if (mapped_toupper != mappedbuf)
+	{
+	  int saved_errno = errno;
+	  free (mapped_toupper);
+	  errno = saved_errno;
+	}
+      goto fail;
+    }
+
+  if (mapped_toupper != mapped_tolower && mapped_toupper != mappedbuf)
+    free (mapped_toupper);
+
+  /* Compare.  */
+  if (!(mapped_length == norms_length
+	&& U_CMP (mapped_tolower, norms, norms_length) == 0))
+    {
+      if (mapped_tolower != mappedbuf)
+	free (mapped_tolower);
+      goto yes;
+    }
+
+  /* Apply totitle mapping.  */
+  mapped_totitle = U_TOTITLE (norms, norms_length, iso639_language, NULL,
+			      mapped_tolower, &mapped_length);
+  if (mapped_totitle == NULL)
+    {
+      if (mapped_tolower != mappedbuf)
+	{
+	  int saved_errno = errno;
+	  free (mapped_tolower);
+	  errno = saved_errno;
+	}
+      goto fail;
+    }
+
+  if (mapped_tolower != mapped_totitle && mapped_tolower != mappedbuf)
+    free (mapped_tolower);
+
+  /* Compare.  */
+  if (!(mapped_length == norms_length
+	&& U_CMP (mapped_totitle, norms, norms_length) == 0))
+    {
+      if (mapped_totitle != mappedbuf)
+	free (mapped_totitle);
+      goto yes;
+    }
+
+  if (mapped_totitle != mappedbuf)
+    free (mapped_totitle);
+  if (norms != normsbuf)
+    free (norms);
+  *resultp = false;
+  return 0;
+
+ yes:
+  if (norms != normsbuf)
+    free (norms);
+  *resultp = true;
+  return 0;
+
+ fail:
+  if (norms != normsbuf)
+    {
+      int saved_errno = errno;
+      free (norms);
+      errno = saved_errno;
+    }
+  return -1;
+}

new file mode 100644
--- /dev/null
+++ b/lib/unicase/u8-is-cased.c
@@ -0,0 +1,36 @@
+/* Test whether case matters for an UTF-8 string.
+   Copyright (C) 2009 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2009.
+
+   This program is free software: you can redistribute it and/or modify it
+   under the terms of the GNU Lesser General Public License as published
+   by the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include "unicase.h"
+
+#include <errno.h>
+#include <stdlib.h>
+
+#include "uninorm.h"
+#include "unistr.h"
+
+#define FUNC u8_is_cased
+#define UNIT uint8_t
+#define U_NORMALIZE u8_normalize
+#define U_TOUPPER u8_toupper
+#define U_TOLOWER u8_tolower
+#define U_TOTITLE u8_totitle
+#define U_CMP u8_cmp
+#include "u-is-cased.h"

new file mode 100644
--- /dev/null
+++ b/modules/unicase/u8-is-cased
@@ -0,0 +1,30 @@
+Description:
+Test whether case matters for an UTF-8 string.
+
+Files:
+lib/unicase/u8-is-cased.c
+lib/unicase/u-is-cased.h
+
+Depends-on:
+unicase/base
+unicase/u8-toupper
+unicase/u8-tolower
+unicase/u8-totitle
+uninorm/u8-normalize
+uninorm/nfd
+unistr/u8-cmp
+
+configure.ac:
+
+Makefile.am:
+lib_SOURCES += unicase/u8-is-cased.c
+
+Include:
+"unicase.h"
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible
+