diff --git a/ChangeLog b/ChangeLog
index 382c39dae2..1b59768056 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Jan 23 22:14:28 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* enc/trans/japanese.c (rb_from_Windows_31J, rb_to_Windows_31J):
+	  provisional workaround for Windows-31J.  [ruby-dev:33320]
+
 Wed Jan 23 15:25:04 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* time.c (time_strftime): copy encoding from format.  [ruby-dev:33303]
diff --git a/enc/trans/japanese.c b/enc/trans/japanese.c
index f4f28ddea2..e523ca7100 100644
--- a/enc/trans/japanese.c
+++ b/enc/trans/japanese.c
@@ -4427,6 +4427,11 @@ rb_from_SHIFT_JIS = {
     "SHIFT_JIS", "UTF-8", &from_SHIFT_JIS, 3, 0,
     NULL, NULL,
 };
+static const rb_transcoder
+rb_from_Windows_31J = {
+    "Windows-31J", "UTF-8", &from_SHIFT_JIS, 3, 0,
+    NULL, NULL,
+};
 
 static const unsigned char
 to_SHIFT_JIS_C2_offsets[64] = {
@@ -13357,6 +13362,11 @@ rb_to_SHIFT_JIS = {
     "UTF-8", "SHIFT_JIS", &to_SHIFT_JIS, 2, 1,
     NULL, NULL,
 };
+static const rb_transcoder
+rb_to_Windows_31J = {
+    "UTF-8", "Windows_31J", &to_SHIFT_JIS, 2, 1,
+    NULL, NULL,
+};
 
 static const unsigned char
 from_EUC_JP_8E_offsets[256] = {
@@ -23860,8 +23870,10 @@ void
 Init_japanese(void)
 {
     rb_register_transcoder(&rb_from_SHIFT_JIS);
+    rb_register_transcoder(&rb_from_Windows_31J);
     rb_register_transcoder(&rb_from_EUC_JP);
     rb_register_transcoder(&rb_to_SHIFT_JIS);
+    rb_register_transcoder(&rb_to_Windows_31J);
     rb_register_transcoder(&rb_to_EUC_JP);
     rb_register_transcoder(&rb_from_ISO_2022_JP);
     rb_register_transcoder(&rb_to_ISO_2022_JP);