--- linux-2.6.9/include/asm-i386/mach-xen/asm/page.h.orig	2009-03-19 13:50:46.165560000 -0700
+++ linux-2.6.9/include/asm-i386/mach-xen/asm/page.h	2009-03-19 14:10:09.602532000 -0700
@@ -9,7 +9,7 @@
 #define PAGE_MASK	(~(PAGE_SIZE-1))
 
 #ifdef CONFIG_X86_PAE
-#define __PHYSICAL_MASK_SHIFT	36
+#define __PHYSICAL_MASK_SHIFT	40
 #define __PHYSICAL_MASK		((1ULL << __PHYSICAL_MASK_SHIFT) - 1)
 #define PHYSICAL_PAGE_MASK	(~((1ULL << PAGE_SHIFT) - 1) & __PHYSICAL_MASK)
 #else