Translate language_en.xml to your language and save as language_xx.xml (xx is taking 
the 2-letter language abbreviation from the ISO Standard 639).

Note:
  the language_xx.xml must use UTF-8 encoding. You can choose the encoding in Save As
  dialog box if you use notepad edit language_xx.xml.

Translate text value between <xx></xx> tag, For example:
========================================================
    <CheckBox_Preview>
      <Caption>&amp;Preview</Caption>
    </CheckBox_Preview>

    ==>

    <CheckBox_Preview>
      <Caption>&amp;XXXXXXXXX</Caption>
    </CheckBox_Preview>
========================================================
Note: "&amp;" is hotkeys sign.

Note: Please use both your language name and your language name in english to translate text value 
      between <language>English</language> tag.

for example:
========================================================
  <info>
    <language>English</language>
  </info>

  ==>

  <info>
    <language>Italiano (Italian)</language>
  </info>
========================================================

If you would like to share your translation, please mail yours to eunqcom@gmail.com,
Thank you very much.

http://eunq.com

ISO 639: 2-letter codes ( http://www.w3.org/WAI/ER/IG/ert/iso639.htm )
=======================================================================
AA "Afar"
AB "Abkhazian"
AF "Afrikaans"
AM "Amharic"
AR "Arabic"
AS "Assamese"
AY "Aymara"
AZ "Azerbaijani"
BA "Bashkir"
BE "Byelorussian"
BG "Bulgarian"
BH "Bihari"
BI "Bislama"
BN "Bengali" "Bangla"
BO "Tibetan"
BR "Breton"
CA "Catalan"
CO "Corsican"
CS "Czech"
CY "Welsh"
DA "Danish"
DE "German"
DZ "Bhutani"
EL "Greek"
EN "English" "American"
EO "Esperanto"
ES "Spanish"
ET "Estonian"
EU "Basque"
FA "Persian"
FI "Finnish"
FJ "Fiji"
FO "Faeroese"
FR "French"
FY "Frisian"
GA "Irish"
GD "Gaelic" "Scots Gaelic"
GL "Galician"
GN "Guarani"
GU "Gujarati"
HA "Hausa"
HI "Hindi"
HR "Croatian"
HU "Hungarian"
HY "Armenian"
IA "Interlingua"
IE "Interlingue"
IK "Inupiak"
IN "Indonesian"
IS "Icelandic"
IT "Italian"
IW "Hebrew"
JA "Japanese"
JI "Yiddish"
JW "Javanese"
KA "Georgian"
KK "Kazakh"
KL "Greenlandic"
KM "Cambodian"
KN "Kannada"
KO "Korean"
KS "Kashmiri"
KU "Kurdish"
KY "Kirghiz"
LA "Latin"
LN "Lingala"
LO "Laothian"
LT "Lithuanian"
LV "Latvian" "Lettish"
MG "Malagasy"
MI "Maori"
MK "Macedonian"
ML "Malayalam"
MN "Mongolian"
MO "Moldavian"
MR "Marathi"
MS "Malay"
MT "Maltese"
MY "Burmese"
NA "Nauru"
NE "Nepali"
NL "Dutch"
NO "Norwegian"
OC "Occitan"
OM "Oromo" "Afan"
OR "Oriya"
PA "Punjabi"
PL "Polish"
PS "Pashto" "Pushto"
PT "Portuguese"
QU "Quechua"
RM "Rhaeto-Romance"
RN "Kirundi"
RO "Romanian"
RU "Russian"
RW "Kinyarwanda"
SA "Sanskrit"
SD "Sindhi"
SG "Sangro"
SH "Serbo-Croatian"
SI "Singhalese"
SK "Slovak"
SL "Slovenian"
SM "Samoan"
SN "Shona"
SO "Somali"
SQ "Albanian"
SR "Serbian"
SS "Siswati"
ST "Sesotho"
SU "Sudanese"
SV "Swedish"
SW "Swahili"
TA "Tamil"
TE "Tegulu"
TG "Tajik"
TH "Thai"
TI "Tigrinya"
TK "Turkmen"
TL "Tagalog"
TN "Setswana"
TO "Tonga"
TR "Turkish"
TS "Tsonga"
TT "Tatar"
TW "Twi"
UK "Ukrainian"
UR "Urdu"
UZ "Uzbek"
VI "Vietnamese"
VO "Volapuk"
WO "Wolof"
XH "Xhosa"
YO "Yoruba"
ZH "Chinese"
ZU "Zulu"