diff --git a/ChangeLog b/ChangeLog
index 02030de8c..6a258bc28 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,11 @@
+2007-12-20  Matthias Clasen  <mclasen@redhat.com>
+
+	* glib/gchecksum.[hc] (g_checksum_new): Return NULL when 
+	the checksum_type is unknown.  (#501853)
+
 2007-12-20  Christian Persch  <chpe@gnome.org>
 
-	* glib/gchecksum.c: (g_checksum_new): Use g_slice_new0, to fix
+	* glib/gchecksum.c (g_checksum_new): Use g_slice_new0, to fix
 	"conditional jump or move depends on uninitialised value(s)" error
 	from valgrind. Bug #504527.
 
diff --git a/glib/gchecksum.c b/glib/gchecksum.c
index e6783de06..bda38b829 100644
--- a/glib/gchecksum.c
+++ b/glib/gchecksum.c
@@ -1052,9 +1052,9 @@ sha256_sum_digest (Sha256sum *sha256,
  * g_checksum_type_get_length:
  * @checksum_type: a #GChecksumType
  *
- * Gets the length in bytes of digests of type @type
+ * Gets the length in bytes of digests of type @checksum_type
  *
- * Return value: the checksum length, or -1 if @type is
+ * Return value: the checksum length, or -1 if @checksum_type is
  * not supported.
  * 
  * Since: 2.16
@@ -1087,8 +1087,9 @@ g_checksum_type_get_length (GChecksumType checksum_type)
  * g_checksum_new:
  * @checksum_type: the desired type of checksum
  *
- * Creates a new #GChecksum, using the checksum algorithm @type. A
- * #GChecksum can be used to compute the checksum, or digest, of an
+ * Creates a new #GChecksum, using the checksum algorithm @checksum_type. 
+ * If the @checksum_type is not known, %NULL is returned.
+ * A #GChecksum can be used to compute the checksum, or digest, of an
  * arbitrary binary blob, using different hashing algorithms.
  *
  * A #GChecksum works by feeding a binary blob through g_checksum_update()
@@ -1100,8 +1101,8 @@ g_checksum_type_get_length (GChecksumType checksum_type)
  * will be closed and it won't be possible to call g_checksum_update()
  * on it anymore.
  *
- * Return value: the newly created #GChecksum. Use g_checksum_free() to
- *   free the memory allocated by it.
+ * Return value: the newly created #GChecksum, or %NULL. 
+ *   Use g_checksum_free() to free the memory allocated by it.
  *
  * Since: 2.16
  */
@@ -1110,7 +1111,8 @@ g_checksum_new (GChecksumType checksum_type)
 {
   GChecksum *checksum;
 
-  g_return_val_if_fail (IS_VALID_TYPE (checksum_type), NULL);
+  if (! IS_VALID_TYPE (checksum_type))
+    return NULL;
 
   checksum = g_slice_new0 (GChecksum);
   checksum->type = checksum_type;
diff --git a/glib/gchecksum.h b/glib/gchecksum.h
index efa0e1b65..7450d7807 100644
--- a/glib/gchecksum.h
+++ b/glib/gchecksum.h
@@ -34,8 +34,8 @@ G_BEGIN_DECLS
  * The hashing algorithm to be used by #GChecksum when performing the
  * digest of some data.
  *
- * The #GChecksumType enumeration can be extended at later date to include
- * new hashing algorithm types.
+ * Note that the #GChecksumType enumeration may be extended at a later 
+ * date to include new hashing algorithm types. 
  *
  * Since: 2.16
  */