diff -ru grub-0.97_orig/stage1/stage1.S grub-0.97/stage1/stage1.S
--- grub-0.97_orig/stage1/stage1.S	2005-02-15 22:54:31.000000000 +0100
+++ grub-0.97/stage1/stage1.S	2007-06-28 18:28:37.000000000 +0200
@@ -114,31 +114,41 @@
 	 * possible boot drive. If GRUB is installed into a floppy,
 	 * this does nothing (only jump).
 	 */
-boot_drive_check:	
+/*boot_drive_check:	
 	jmp	1f
 	testb	$0x80, %dl
 	jnz	1f
-	movb	$0x80, %dl
+	movb	$0x80, %dl*/
 1:	
 
 	/*
 	 * ljmp to the next instruction because some bogus BIOSes
 	 * jump to 07C0:0000 instead of 0000:7C00.
 	 */
-	ljmp	$0, $ABS(real_start)
+	/*ljmp	$0, $ABS(real_start)*/
 
 real_start:	
 
-	/* set up %ds and %ss as offset from 0 */
-	xorw	%ax, %ax
-	movw	%ax, %ds
-	movw	%ax, %ss
-
 	/* set up the REAL stack */
 	movw	$STAGE1_STACKSEG, %sp
 
 	sti		/* we're safe again */
 
+  /* mac pro hack*/
+  push   %edx
+  mov    $0x8000fa90, %eax
+  mov    $0xcf8, %dx
+  out    %eax, (%dx)
+  mov    $0x40, %al
+  mov    $0xcfc, %dx
+  out    %al, (%dx)
+  pop    %edx
+
+	/* set up %ds and %ss as offset from 0 */
+	xorl	%eax, %eax
+	movw	%ax, %ds
+	movw	%ax, %ss
+
 	/*
 	 *  Check if we have a forced disk reference here
 	 */