=== modified file 'grub-core/boot/i386/pc/boot.S'
--- grub-core/boot/i386/pc/boot.S	2010-09-19 22:06:45 +0000
+++ grub-core/boot/i386/pc/boot.S	2010-12-17 04:27:12 +0000
@@ -407,11 +407,13 @@
 	ret
 
 	/*
-	 *  Windows NT breaks compatibility by embedding a magic
-	 *  number here.
+	 *  Windows NT uses this as a 32-bit Volume Id that is unique
+	 *  amoung disks connected to the system and needs to be
+	 *  preserved. LILO acts similarly, using this field to locate
+	 *  the disks with its second stage.
 	 */
 
-	. = _start + GRUB_BOOT_MACHINE_WINDOWS_NT_MAGIC
+	. = _start + GRUB_BOOT_MACHINE_X86_VOLID
 nt_magic:
 	.long 0
 	.word 0

=== modified file 'include/grub/i386/pc/boot.h'
--- include/grub/i386/pc/boot.h	2010-04-26 08:56:12 +0000
+++ include/grub/i386/pc/boot.h	2010-12-12 06:22:16 +0000
@@ -39,8 +39,8 @@
 /* The offset of BOOT_DRIVE_CHECK.  */
 #define GRUB_BOOT_MACHINE_DRIVE_CHECK	0x66
 
-/* The offset of a magic number used by Windows NT.  */
-#define GRUB_BOOT_MACHINE_WINDOWS_NT_MAGIC	0x1b8
+/* The offset of what is used as a Volume Id by Windows NT and LILO.	*/
+#define GRUB_BOOT_MACHINE_X86_VOLID	0x1b8
 
 /* The offset of the start of the partition table.  */
 #define GRUB_BOOT_MACHINE_PART_START	0x1be

=== modified file 'util/grub-setup.c'
--- util/grub-setup.c	2010-11-26 21:03:16 +0000
+++ util/grub-setup.c	2010-12-12 06:19:44 +0000
@@ -396,9 +396,9 @@
 
     /* Copy the partition table.  */
     if (dest_partmap)
-      memcpy (boot_img + GRUB_BOOT_MACHINE_WINDOWS_NT_MAGIC,
-	      tmp_img + GRUB_BOOT_MACHINE_WINDOWS_NT_MAGIC,
-	      GRUB_BOOT_MACHINE_PART_END - GRUB_BOOT_MACHINE_WINDOWS_NT_MAGIC);
+      memcpy (boot_img + GRUB_BOOT_MACHINE_X86_VOLID,
+	      tmp_img + GRUB_BOOT_MACHINE_X86_VOLID,
+	      GRUB_BOOT_MACHINE_PART_END - GRUB_BOOT_MACHINE_X86_VOLID);
 
     free (tmp_img);