diff --git a/mps/code/mpscmfs.h b/mps/code/mpscmfs.h
new file mode 100644
index 00000000000..4a46e10a84b
--- /dev/null
+++ b/mps/code/mpscmfs.h
@@ -0,0 +1,56 @@
+/* mpscamfs.h: MEMORY POOL SYSTEM CLASS "MFS"
+ *
+ * $Id$
+ * Copyright (c) 2001-2012 Ravenbrook Limited.  See end of file for license.
+ */
+
+#ifndef mpscmfs_h
+#define mpscmfs_h
+
+#include "mps.h"
+
+extern mps_class_t mps_class_mfs(void);
+
+#endif /* mpscmfs_h */
+
+
+/* C. COPYRIGHT AND LICENSE
+ *
+ * Copyright (C) 2001-2012 Ravenbrook Limited <http://www.ravenbrook.com/>.
+ * All rights reserved.  This is an open source license.  Contact
+ * Ravenbrook for commercial licensing options.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 
+ * 3. Redistributions in any form must be accompanied by information on how
+ * to obtain complete source code for this software and any accompanying
+ * software that uses this software.  The source code must either be
+ * included in the distribution or be available for no more than the cost
+ * of distribution plus a nominal fee, and must be freely redistributable
+ * under reasonable conditions.  For an executable file, complete source
+ * code means the source code for all modules it contains. It does not
+ * include source code for modules or files that typically accompany the
+ * major components of the operating system on which the executable file
+ * runs.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+ * PURPOSE, OR NON-INFRINGEMENT, ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDERS AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
diff --git a/mps/code/poolmfs.c b/mps/code/poolmfs.c
index 82044e37589..ad4140a4479 100644
--- a/mps/code/poolmfs.c
+++ b/mps/code/poolmfs.c
@@ -1,7 +1,7 @@
 /* poolmfs.c: MANUAL FIXED SMALL UNIT POOL
  *
  * $Id$
- * Copyright (c) 2001 Ravenbrook Limited.  See end of file for license.
+ * Copyright (c) 2001-2012 Ravenbrook Limited.  See end of file for license.
  *
  * This is the implementation of the MFS pool class.
  *
@@ -32,6 +32,7 @@
  */
 
 
+#include "mpscmfs.h"
 #include "poolmfs.h"
 #include "mpm.h"
 
@@ -282,6 +283,12 @@ PoolClass PoolClassMFS(void)
 }
 
 
+mps_class_t mps_class_mfs(void)
+{
+  return (mps_class_t)PoolClassMFS();
+}
+
+
 Bool MFSCheck(MFS mfs)
 {
   Arena arena;
@@ -305,7 +312,7 @@ Bool MFSCheck(MFS mfs)
 
 /* C. COPYRIGHT AND LICENSE
  *
- * Copyright (C) 2001-2002 Ravenbrook Limited <http://www.ravenbrook.com/>.
+ * Copyright (C) 2001-2012 Ravenbrook Limited <http://www.ravenbrook.com/>.
  * All rights reserved.  This is an open source license.  Contact
  * Ravenbrook for commercial licensing options.
  * 
diff --git a/mps/manual/source/pool/mfs.rst b/mps/manual/source/pool/mfs.rst
index d77ede12c41..b1a78a9e5cf 100644
--- a/mps/manual/source/pool/mfs.rst
+++ b/mps/manual/source/pool/mfs.rst
@@ -82,14 +82,14 @@ MFS interface
 
         mps_res_t mps_pool_create(mps_pool_t *pool_o, mps_arena_t arena, 
                                   mps_class_t mps_class_mfs(),
-                                  mps_size_t unit_size,
-                                  mps_size_t extend_size)
-
-    ``unit_size`` is the :term:`size` of blocks that will be allocated
-    from this pool, in :term:`bytes (1)`. It must be at least one
-    :term:`word`.
+                                  mps_size_t extend_size,
+                                  mps_size_t unit_size)
 
     ``extend_size`` is the :term:`size` of segment that the pool will
     request from the :term:`arena`. It must be at least as big as
     ``unit_size``. If this is not a multiple of ``unit_size``, there
     will be wasted space in each segment.
+
+    ``unit_size`` is the :term:`size` of blocks that will be allocated
+    from this pool, in :term:`bytes (1)`. It must be at least one
+    :term:`word`.