diff --git a/src/ptrace/_UPT_reg_offset.c b/src/ptrace/_UPT_reg_offset.c
index b00efa77..916baae5 100644
--- a/src/ptrace/_UPT_reg_offset.c
+++ b/src/ptrace/_UPT_reg_offset.c
@@ -1,5 +1,5 @@
 /* libunwind - a platform-independent unwind library
-   Copyright (C) 2003 Hewlett-Packard Co
+   Copyright (C) 2003-2004 Hewlett-Packard Co
 	Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
 
 This file is part of libunwind.
@@ -228,6 +228,28 @@ int _UPT_reg_offset[UNW_REG_LAST + 1] =
 /*  ORIG_EAX		= 0x2c, */
 /*  EFLAGS		= 0x38, */
 /*  SS			= 0x40 */
+#elif defined(UNW_TARGET_X86_64)
+    [UNW_X86_64_RAX]	= 0x50,
+    [UNW_X86_64_RDX]	= 0x60,
+    [UNW_X86_64_RCX]	= 0x58,
+    [UNW_X86_64_RBX]	= 0x28,
+    [UNW_X86_64_RSI]	= 0x68,
+    [UNW_X86_64_RDI]	= 0x70,
+    [UNW_X86_64_RBP]	= 0x24,
+    [UNW_X86_64_RSP]	= 0x98,
+    [UNW_X86_64_R8]	= 0x48,
+    [UNW_X86_64_R9]	= 0x40,
+    [UNW_X86_64_R10]	= 0x38,
+    [UNW_X86_64_R11]	= 0x30,
+    [UNW_X86_64_R12]	= 0x18,
+    [UNW_X86_64_R13]	= 0x10,
+    [UNW_X86_64_R14]	= 0x08,
+    [UNW_X86_64_R15]	= 0x00,
+    [UNW_X86_64_RIP]	= 0x80
+//  [UNW_X86_64_CS]	= 0x88,
+//  [UNW_X86_64_EFLAGS]	= 0x90,
+//  [UNW_X86_64_RSP]	= 0x98,
+//  [UNW_X86_64_SS]	= 0xa0
 #else
 # error Fix me.
 #endif