Straight from xen-unstable.hg csets:

changeset:   15146:1e418f7e0212
user:        kfraser@localhost.localdomain
date:        Thu May 24 13:34:19 2007 +0100
summary:     vnc: Fix Zenkaku_Hankaku and add deadkey keysyms

changeset:   15446:f85252ce203e
user:        kfraser@localhost.localdomain
date:        Tue Jul 03 10:06:48 2007 +0100
summary:     hvm: Fix keymap for Windows keys.

changeset:   15474:2dee920e0fd7
user:        kfraser@localhost.localdomain
date:        Fri Jul 06 14:37:47 2007 +0100
summary:     hvm: Fix vnc keymap for Japanese keyboards.

Despite the summaries, this affects PVFB as well as HVM.

diff -rup a/tools/ioemu/keymaps/ja b/tools/ioemu/keymaps/ja
--- a/tools/ioemu/keymaps/ja	2007-05-18 16:45:21.000000000 +0200
+++ b/tools/ioemu/keymaps/ja	2007-07-13 18:48:11.000000000 +0200
@@ -100,6 +100,7 @@ backslash 0x73
 bar 0x7d shift
 underscore 0x73 shift
 Henkan_Mode 0x79
+Katakana_Real 0x70
 Katakana 0x70
 Muhenkan 0x7b
 Henkan_Mode_Real 0x79
diff -rup a/tools/ioemu/keymaps/modifiers b/tools/ioemu/keymaps/modifiers
--- a/tools/ioemu/keymaps/modifiers	2007-05-18 16:45:21.000000000 +0200
+++ b/tools/ioemu/keymaps/modifiers	2007-07-13 15:54:10.000000000 +0200
@@ -11,8 +11,8 @@ Control_L 0x1d
 
 # Translate Super to Windows keys. 
 # This is hardcoded. See documentation for details. 
-Super_R 0xdb
-Super_L 0xdc
+Super_R 0xdc
+Super_L 0xdb
 
 # Translate Menu to the Windows Application key. 
 Menu 0xdd
diff -rup a/tools/ioemu/vnc_keysym.h b/tools/ioemu/vnc_keysym.h
--- a/tools/ioemu/vnc_keysym.h	2007-05-18 16:45:21.000000000 +0200
+++ b/tools/ioemu/vnc_keysym.h	2007-07-24 20:58:53.000000000 +0200
@@ -290,11 +290,37 @@ static name2keysym_t name2keysym[]={
     /* localized keys */
 {"BackApostrophe", 0xff21},
 {"Muhenkan", 0xff22},
-{"Katakana", 0xff25},
-{"Zenkaku_Hankaku", 0xff29},
+{"Katakana", 0xff27},
+{"Hankaku", 0xff29},
+{"Zenkaku_Hankaku", 0xff2a},
 {"Henkan_Mode_Real", 0xff23},
 {"Henkan_Mode_Ultra", 0xff3e},
 {"backslash_ja", 0xffa5},
+{"Katakana_Real", 0xff25},
+{"Eisu_toggle", 0xff30},
+
+    /* dead keys */
+{"dead_grave", 0xfe50},
+{"dead_acute", 0xfe51},
+{"dead_circumflex", 0xfe52},
+{"dead_tilde", 0xfe53},
+{"dead_macron", 0xfe54},
+{"dead_brev", 0xfe55},
+{"dead_abovedot", 0xfe56},
+{"dead_diaeresis", 0xfe57},
+{"dead_abovering", 0xfe58},
+{"dead_doubleacute", 0xfe59},
+{"dead_caron", 0xfe5a},
+{"dead_cedilla", 0xfe5b},
+{"dead_ogonek", 0xfe5c},
+{"dead_iota", 0xfe5d},
+{"dead_voiced_sound", 0xfe5e},
+{"dead_semivoiced_sound", 0xfe5f},
+{"dead_belowdot", 0xfe60},
+{"dead_hook", 0xfe61},
+{"dead_horn", 0xfe62},
+
 
 {0,0},
 };
+