diff --git a/po/ChangeLog b/po/ChangeLog
index 5fa6552..8bc07ef 100644
--- a/po/ChangeLog
+++ b/po/ChangeLog
@@ -1,3 +1,8 @@
+2010-03-08  Bruno Haible  <bruno@clisp.org>
+
+	* ja.po: New file, from Yasuaki Taniguchi <yasuakit@gmail.com>.
+	* LINGUAS: Add ja.
+
 2009-12-06  Bruno Haible  <bruno@clisp.org>
 
 	* da.po: Update from Keld Simonsen <keld@keldix.com>.
diff --git a/po/LINGUAS b/po/LINGUAS
index bbebba8..b3632d5 100644
--- a/po/LINGUAS
+++ b/po/LINGUAS
@@ -1,2 +1,2 @@
 # Set of available languages.
-af bg ca cs da de el eo es et fi fr ga gl hr hu id it nl pl pt_BR rm ro ru sk sl sq sr sv tr uk vi wa zh_CN zh_TW
+af bg ca cs da de el eo es et fi fr ga gl hr hu id it ja nl pl pt_BR rm ro ru sk sl sq sr sv tr uk vi wa zh_CN zh_TW
diff --git a/po/ja.po b/po/ja.po
new file mode 100644
index 0000000..12e8bff
--- /dev/null
+++ b/po/ja.po
@@ -0,0 +1,340 @@
+# Japanese message of libiconv
+# Copyright (C) 2010 Free Software Foundation, Inc.
+# This file is distributed under the same license as the libiconv package.
+# Yasuaki Taniguchi <yasuakit@gmail.com>, 2010.
+msgid ""
+msgstr ""
+"Project-Id-Version: GNU libiconv 1.12\n"
+"Report-Msgid-Bugs-To: bug-gnu-libiconv@gnu.org\n"
+"POT-Creation-Date: 2009-06-30 22:53+0200\n"
+"PO-Revision-Date: 2010-03-08 12:20+0900\n"
+"Last-Translator: Yasuaki Taniguchi <yasuakit@gmail.com>\n"
+"Language-Team: Japanese <translation-team-ja@lists.sourceforge.net>\n"
+"Language: ja\n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=UTF-8\n"
+"Content-Transfer-Encoding: 8bit\n"
+"Plural-Forms: nplurals=1; plural=0;\n"
+
+#. TRANSLATORS: The first line of the short usage message.
+#: src/iconv.c:103
+msgid "Usage: iconv [-c] [-s] [-f fromcode] [-t tocode] [file ...]"
+msgstr ""
+"使用法: iconv [-c] [-s] [-f 変換元コード] [-t 変換先コード] [ファイル名 ...]"
+
+#. TRANSLATORS: The second line of the short usage message.
+#. Align it correctly against the first line.
+#: src/iconv.c:107
+msgid "or:    iconv -l"
+msgstr "または:    iconv -l"
+
+#: src/iconv.c:109
+#, c-format
+msgid "Try `%s --help' for more information.\n"
+msgstr "さらに情報が必要な場合は `%s --help' と入力してください。\n"
+
+#. TRANSLATORS: The first line of the long usage message.
+#. The %s placeholder expands to the program name.
+#: src/iconv.c:114
+#, c-format, no-wrap
+msgid "Usage: %s [OPTION...] [-f ENCODING] [-t ENCODING] [INPUTFILE...]\n"
+msgstr "使用法: %s [オプション...] [-f 文字コード] [-t 文字コード] [入力ファイル...]\n"
+
+#. TRANSLATORS: The second line of the long usage message.
+#. Align it correctly against the first line.
+#. The %s placeholder expands to the program name.
+#: src/iconv.c:121
+#, c-format, no-wrap
+msgid "or:    %s -l\n"
+msgstr "または:    %s -l\n"
+
+#. TRANSLATORS: Description of the iconv program.
+#: src/iconv.c:127
+#, c-format, no-wrap
+msgid "Converts text from one encoding to another encoding.\n"
+msgstr "ある文字コードから別の文字コードへテキストを変換します。\n"
+
+#: src/iconv.c:131
+#, c-format, no-wrap
+msgid "Options controlling the input and output format:\n"
+msgstr "入出力形式を制御するオプション:\n"
+
+#: src/iconv.c:134
+#, c-format, no-wrap
+msgid ""
+"  -f ENCODING, --from-code=ENCODING\n"
+"                              the encoding of the input\n"
+msgstr ""
+"  -f 文字コード, --from-code=文字コード\n"
+"                              入力の文字コード\n"
+
+#: src/iconv.c:138
+#, c-format, no-wrap
+msgid ""
+"  -t ENCODING, --to-code=ENCODING\n"
+"                              the encoding of the output\n"
+msgstr ""
+"  -t 文字コード, --to-code=文字コード\n"
+"                              出力の文字コード\n"
+
+#: src/iconv.c:143
+#, c-format, no-wrap
+msgid "Options controlling conversion problems:\n"
+msgstr "返還の問題を制御するオプション:\n"
+
+#: src/iconv.c:146
+#, c-format, no-wrap
+msgid "  -c                          discard unconvertible characters\n"
+msgstr "  -c                          変換できない文字を破棄する\n"
+
+#: src/iconv.c:149
+#, c-format, no-wrap
+msgid ""
+"  --unicode-subst=FORMATSTRING\n"
+"                              substitution for unconvertible Unicode characters\n"
+msgstr ""
+"  --unicode-subst=書式文字列\n"
+"                              変換できない Unicode 文字の置換\n"
+
+#: src/iconv.c:153
+#, c-format, no-wrap
+msgid "  --byte-subst=FORMATSTRING   substitution for unconvertible bytes\n"
+msgstr "  --byte-subst=書式文字列   変換できないバイトの置換\n"
+
+#: src/iconv.c:156
+#, c-format, no-wrap
+msgid ""
+"  --widechar-subst=FORMATSTRING\n"
+"                              substitution for unconvertible wide characters\n"
+msgstr ""
+"  --widechar-subst=書式文字列\n"
+"                              変換できないワイド文字の置換\n"
+
+#: src/iconv.c:161
+#, c-format, no-wrap
+msgid "Options controlling error output:\n"
+msgstr "エラー出力を制御するオプション:\n"
+
+#: src/iconv.c:164
+#, c-format, no-wrap
+msgid "  -s, --silent                suppress error messages about conversion problems\n"
+msgstr "  -s, --silent                変換問題のエラーメッセージ出力を抑止する\n"
+
+#: src/iconv.c:168
+#, c-format, no-wrap
+msgid "Informative output:\n"
+msgstr "情報の出力:\n"
+
+#: src/iconv.c:171
+#, c-format, no-wrap
+msgid "  -l, --list                  list the supported encodings\n"
+msgstr "  -l, --list                  サポートする文字コード一覧を表示する\n"
+
+#: src/iconv.c:174
+#, c-format, no-wrap
+msgid "  --help                      display this help and exit\n"
+msgstr "  --help                      このヘルプを表示して終了する\n"
+
+#: src/iconv.c:177
+#, c-format, no-wrap
+msgid "  --version                   output version information and exit\n"
+msgstr "  --version                   バージョン情報を表示して終了する\n"
+
+#. TRANSLATORS: The placeholder indicates the bug-reporting address
+#. for this package.  Please add _another line_ saying
+#. "Report translation bugs to <...>\n" with the address for translation
+#. bugs (typically your translation team's web or email address).
+#: src/iconv.c:184
+msgid "Report bugs to <bug-gnu-libiconv@gnu.org>.\n"
+msgstr ""
+"バグレポート先 <bug-gnu-libiconv@gnu.org>\n"
+"翻訳問題レポート先 <translation-team-ja@lists.sourceforge.net>\n"
+
+#: src/iconv.c:195
+#, fuzzy, no-wrap
+msgid ""
+"License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>\n"
+"This is free software: you are free to change and redistribute it.\n"
+"There is NO WARRANTY, to the extent permitted by law.\n"
+msgstr ""
+"License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>\n"
+"This is free software: you are free to change and redistribute it.\n"
+"There is NO WARRANTY, to the extent permitted by law.\n"
+
+#. TRANSLATORS: The %s placeholder expands to an author's name.
+#: src/iconv.c:201
+#, c-format
+msgid "Written by %s.\n"
+msgstr "作成者 %s.\n"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a command-line option.
+#: src/iconv.c:295
+#, c-format
+msgid ""
+"%s argument: A format directive with a variable width is not allowed here."
+msgstr "引数 %s : ここでは可変幅の書式指定を使用できません。"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a command-line option.
+#: src/iconv.c:310
+#, c-format
+msgid ""
+"%s argument: A format directive with a variable precision is not allowed "
+"here."
+msgstr "引数 %s : ここでは可変精度の書式指定を使用できません。"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a command-line option.
+#: src/iconv.c:326
+#, c-format
+msgid "%s argument: A format directive with a size is not allowed here."
+msgstr "引数 %s : ここではサイズ指定を行う書式指定を使用できません。"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a command-line option.
+#: src/iconv.c:368
+#, c-format
+msgid "%s argument: The string ends in the middle of a directive."
+msgstr "引数 %s : 書式指定の中間で文字列が終了しました。"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a command-line option.
+#. The %c placeholder expands to an unknown format directive.
+#: src/iconv.c:375
+#, c-format
+msgid "%s argument: The character '%c' is not a valid conversion specifier."
+msgstr "引数 %s : 文字 '%c' は無効な変換指定です。"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a command-line option.
+#: src/iconv.c:381
+#, c-format
+msgid ""
+"%s argument: The character that terminates the format directive is not a "
+"valid conversion specifier."
+msgstr "引数 %s : 書式指定を終端させる文字は有効な変換指定ではありません。"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a command-line option.
+#. The %u placeholder expands to the number of arguments consumed by the format string.
+#: src/iconv.c:397
+#, c-format
+msgid ""
+"%s argument: The format string consumes more than one argument: %u argument."
+msgid_plural ""
+"%s argument: The format string consumes more than one argument: %u arguments."
+msgstr[0] "引数 %s : 書式文字列が2つ以上の引数を消費します: %u 個の引数。"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a piece of text, specified through --byte-subst.
+#: src/iconv.c:455
+#, c-format
+msgid "cannot convert byte substitution to Unicode: %s"
+msgstr "バイトから Unicode へ置換をおこなう変換ができません: %s"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a piece of text, specified through --unicode-subst.
+#: src/iconv.c:495
+#, c-format
+msgid "cannot convert unicode substitution to target encoding: %s"
+msgstr "Unicodeから変換先文字コードへの置換を行う変換ができません: %s"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a piece of text, specified through --byte-subst.
+#: src/iconv.c:536
+#, c-format
+msgid "cannot convert byte substitution to wide string: %s"
+msgstr "バイトからワイド文字への置換を行う変換ができません: %s"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a piece of text, specified through --widechar-subst.
+#: src/iconv.c:577
+#, c-format
+msgid "cannot convert widechar substitution to target encoding: %s"
+msgstr "ワイド文字から変換先文字コードへの置換を行う変換ができません: %s"
+
+#. TRANSLATORS: An error message.
+#. The %s placeholder expands to a piece of text, specified through --byte-subst.
+#: src/iconv.c:618
+#, c-format
+msgid "cannot convert byte substitution to target encoding: %s"
+msgstr "バイトから変換先文字コードへ置換を行う変換ができません: %s"
+
+#. TRANSLATORS: An error message.
+#. The placeholders expand to the input file name, a line number, and a column number.
+#: src/iconv.c:637
+#, c-format
+msgid "%s:%u:%u: cannot convert"
+msgstr "%s:%u行:%u列: 変換できません"
+
+#. TRANSLATORS: An error message.
+#. The placeholders expand to the input file name, a line number, and a column number.
+#. A "shift sequence" is a sequence of bytes that changes the state of the converter;
+#. this concept exists only for "stateful" encodings like ISO-2022-JP.
+#: src/iconv.c:651
+#, c-format
+msgid "%s:%u:%u: incomplete character or shift sequence"
+msgstr "%s:%u行:%u列: 不完全な文字またはシフトシーケンスです"
+
+#. TRANSLATORS: The first part of an error message.
+#. It is followed by a colon and a detail message.
+#. The placeholders expand to the input file name, a line number, and a column number.
+#: src/iconv.c:664
+#, c-format
+msgid "%s:%u:%u"
+msgstr "%s:%u行:%u列"
+
+#. TRANSLATORS: An error message.
+#. The placeholder expands to the input file name.
+#: src/iconv.c:819
+#, c-format
+msgid "%s: I/O error"
+msgstr "%s: I/O エラー"
+
+#. TRANSLATORS: An error message.
+#. The placeholder expands to the encoding name, specified through --from-code.
+#: src/iconv.c:1007
+#, c-format
+msgid "conversion from %s unsupported"
+msgstr "%s からの変換はサポートされていません"
+
+#. TRANSLATORS: An error message.
+#. The placeholder expands to the encoding name, specified through --to-code.
+#: src/iconv.c:1013
+#, c-format
+msgid "conversion to %s unsupported"
+msgstr "%s への変換はサポートされていません"
+
+#. TRANSLATORS: An error message.
+#. The placeholders expand to the encoding names, specified through --from-code and --to-code, respectively.
+#: src/iconv.c:1019
+#, c-format
+msgid "conversion from %s to %s unsupported"
+msgstr "%s から %s への変換はサポートされていません"
+
+#. TRANSLATORS: Additional advice after an error message.
+#. The %s placeholder expands to the program name.
+#: src/iconv.c:1024
+#, c-format
+msgid "try '%s -l' to get the list of supported encodings"
+msgstr "サポートする文字コード一覧は '%s -l' と入力してください。"
+
+#. TRANSLATORS: A filename substitute denoting standard input.
+#: src/iconv.c:1081
+msgid "(stdin)"
+msgstr "(標準入力)"
+
+#. TRANSLATORS: The first part of an error message.
+#. It is followed by a colon and a detail message.
+#. The %s placeholder expands to the input file name.
+#: src/iconv.c:1093
+#, c-format
+msgid "%s"
+msgstr "%s"
+
+#. TRANSLATORS: An error message.
+#: src/iconv.c:1107
+#, c-format
+msgid "I/O error"
+msgstr "I/O エラー"