diff -rupN linux-2.6.10.orig/fs/namespace.c linux-2.6.10/fs/namespace.c
--- linux-2.6.10.orig/fs/namespace.c	2005-05-16 10:46:42.000000000 +0300
+++ linux-2.6.10/fs/namespace.c	2005-05-16 10:31:53.000000000 +0300
@@ -407,6 +407,8 @@ int do_umount(struct vfsmount *mnt, int 
 	 */
 
 	lock_kernel();
+	if (sb->s_op->umount_lustre)
+		sb->s_op->umount_lustre(sb);
 	if( (flags&MNT_FORCE) && sb->s_op->umount_begin)
 		sb->s_op->umount_begin(sb);
 	unlock_kernel();
diff -rupN linux-2.6.10.orig/include/linux/fs.h linux-2.6.10/include/linux/fs.h
--- linux-2.6.10.orig/include/linux/fs.h	2005-05-16 10:47:02.000000000 +0300
+++ linux-2.6.10/include/linux/fs.h	2005-05-16 10:32:50.000000000 +0300
@@ -997,6 +997,7 @@ struct super_operations {
 	int (*remount_fs) (struct super_block *, int *, char *);
 	void (*clear_inode) (struct inode *);
 	void (*umount_begin) (struct super_block *);
+	void (*umount_lustre) (struct super_block *);
 
 	int (*show_options)(struct seq_file *, struct vfsmount *);
 };