diff --git a/src/hooks/pre-commit.hook b/src/hooks/pre-commit.hook
index 998388f3..04c2dac0 100755
--- a/src/hooks/pre-commit.hook
+++ b/src/hooks/pre-commit.hook
@@ -73,3 +73,21 @@ echo "==========================================================================
         exit 1
     fi
 fi
+
+
+for file in `git diff-index --cached --name-only HEAD --diff-filter=ACMR| grep "\.po$"` ; do
+    echo "Checking ${file}"
+    nf=`git checkout-index --temp ${file} | cut -f 1`
+    ./src/i18n/helpers/polint.py "${nf}"
+    r=$?
+    rm "${nf}"
+    if [ $r != 0 ] ; then
+echo "================================================================================================="
+echo " Format error in: $file                                                                          "
+echo "                                                                                                 "
+echo " Please fix before committing. Don't forget to run git add before trying to commit again.        "
+echo "                                                                                                 "
+echo "================================================================================================="
+        exit 1
+    fi
+done
diff --git a/src/i18n/Makefile.am b/src/i18n/Makefile.am
index 7602865d..148a9ffd 100644
--- a/src/i18n/Makefile.am
+++ b/src/i18n/Makefile.am
@@ -26,6 +26,7 @@ build: LANGUAGES = $(shell $(FIND) ./ -iname '*.po' -printf '%f\n' | $(SED) 's/\
 build: update
 	@if [ "$(NODEJS_SUPPORT_PO2JSON)" = "no" ]; then echo "Node.js module 'po2json' not found, required when building i18n"; exit 1; fi
 	@if [ "$(PYTHON)" = "" ]; then echo "Command 'python' not found, required when building i18n"; exit 1; fi
+	$(PYTHON) "$(CURDIR)/helpers/polint.py"
 	for lang in $(LANGUAGES) ; do \
 		$(NODEJS) "$(CURDIR)/helpers/po2json" "$(CURDIR)/messages-$$lang.po" "$(ROOT)/static/translation/messages-$$lang.json" ; \
 	done
diff --git a/src/i18n/helpers/polint.py b/src/i18n/helpers/polint.py
new file mode 100755
index 00000000..739f0a62
--- /dev/null
+++ b/src/i18n/helpers/polint.py
@@ -0,0 +1,234 @@
+#!/usr/bin/python -u
+#
+# Helper script to check syntax of translation files.
+#
+# (c)2016 struktur AG
+try:
+    from collections import OrderedDict
+except ImportError:
+    OrderedDict = dict
+import glob
+import os
+import sys
+
+ROOT = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
+
+def parsepo(fn):
+    """
+    Open po file and return a dict containing msgid as keys and msgstr as value.
+    Return None on syntax errors, raise an exception on other errors.
+    """
+    data = OrderedDict()
+    if isinstance(fn, basestring):
+        with file(fn, 'rb') as fp:
+            lines = fp.readlines()
+    else:
+        lines = fn.readlines()
+
+    msgid = None
+    msgstr = None
+    default = None
+    first = True
+    lastline = None
+    untranslated = []
+    errors = 0
+
+    # find end of header
+    for line_number, line in enumerate(lines):
+        try:
+            line = unicode(line, 'utf-8')
+        except UnicodeError:
+            try:
+                line = unicode(line, 'latin-1')
+            except UnicodeError:
+                errors += 1
+                print >> sys.stderr, 'ERROR: Could not decode data in line %d: %r' % (line_number+1, line)
+                continue
+
+        if line[-2:] == '\r\n':
+            errors += 1
+            print >> sys.stderr, 'ERROR: line %d has Windoze line endings' % (line_number+1)
+            line = line[:-2]
+
+        if line[-1:] == '\n':
+            line = line[:-1]
+
+        if line != line.strip():
+            errors += 1
+            print >> sys.stderr, 'ERROR: line %d contains leading and/or trailing whitespaces' % (line_number+1)
+
+        if line.startswith("msgid"):
+            msgid = line.strip()[7:-1]
+            msgstr = None
+        elif line.startswith("msgstr"):
+            msgstr = line.strip()[8:-1]
+        elif line.startswith('"') and msgstr is not None and msgid is not None:
+            msgstr += line.strip()[1:-1]
+        elif line.startswith("#. Default: "):
+            default = line.strip()[13:-1]
+        elif line.startswith("#"):
+            lastline = line
+            continue
+        elif not line:
+            # blank line -> must be finished
+            if msgid is None and msgstr is None:
+                if lastline.startswith('#~'):
+                    lastline = line
+                    continue
+                else:
+                    errors += 1
+                    print >> sys.stderr, 'ERROR: Got blank line in %d without msgstr or msgid.' % (line_number+1)
+                    continue
+
+            if first:
+                # skip first occurance as this is the header
+                first = False
+                lastline = line
+                continue
+
+            if not msgstr:
+                untranslated.append(msgid)
+
+            # set data
+            data[msgid] = (msgstr, default)
+            msgid = msgstr = default = None
+
+            lastline = line
+
+    if msgid is not None and msgstr is not None:
+        # add last line if not followed by empty line
+        if not msgstr:
+            untranslated.append(msgid)
+
+        data[msgid] = (msgstr, default)
+        msgid = msgstr = None
+
+    if errors:
+        return errors, data, untranslated
+
+    return 0, data, untranslated
+
+def check_translation(msgid, msgstr, default, value, language):
+    if not default:
+        default = msgid
+
+    errors = 0
+    if '  ' in value:
+        errors += 1
+        print >> sys.stderr, 'ERROR: Translation for %r contains too many whitespaces (%s)' % (msgid, value)
+
+    start_quote = default and (default.startswith('\\"') or default.startswith('"') \
+                          or default.startswith("'"))
+    if value.startswith('\\"') and not start_quote:
+        print >> sys.stderr, 'ERROR: Translation for %r starts with an " (%s)' % (msgid, value)
+        value = value[2:]
+        errors += 1
+    elif value.startswith('"') and not start_quote:
+        print >> sys.stderr, 'ERROR: Translation for %r starts with an " (%s)' % (msgid, value)
+        value = value[1:]
+        errors += 1
+
+    end_quote = default and (default.endswith('\\"') or default.endswith('"') \
+                        or default.endswith("'"))
+    if value.endswith('\\"') and not end_quote:
+        print >> sys.stderr, 'ERROR: Translation for %r ends with an " (%s)' % (msgid, value)
+        value = value[:-2]
+        errors += 1
+    elif value.endswith('"') and not end_quote:
+        print >> sys.stderr, 'ERROR: Translation for %r ends with an " (%s)' % (msgid, value)
+        value = value[:-1]
+        errors += 1
+
+    leading_space = default and default.startswith(' ')
+    if leading_space and not value.startswith(' '):
+        print >> sys.stderr, 'ERROR: Translation for %r does not start with a leading whitespace (%s)' % (msgid, value)
+        value = ' ' + value
+        errors += 1
+    elif not leading_space and value.startswith(' '):
+        print >> sys.stderr, 'ERROR: Translation for %r starts with a leading whitespace (%s)' % (msgid, value)
+        value = ' ' + value
+        errors += 1
+
+    if not language.startswith('zh') and not language.startswith('ko') and not language.startswith('ja'):
+        # TODO(fancycode): Is it correct to skip for these languages?
+        trailing_dot = default and default.endswith('.')
+        if trailing_dot and not value.endswith('.'):
+            print >> sys.stderr, 'ERROR: Translation for %r does not end with a tailing dot (%s)' % (msgid, value)
+            value += '.'
+            errors += 1
+
+    punct = False
+    for ch in ('.', ',', ';', ':', '?', '!', ')', ']'):
+        if ' '+ch in value and not punct:
+            if ch != '.' or not ' ..' in value:
+                print >> sys.stderr, 'ERROR: Translation for %r contains invalid punctuation (%s)' % (msgid, value)
+                punct = True
+                errors += 1
+
+            while ' '+ch+' ' in value:
+                value = value.replace(' '+ch+' ', ch+' ')
+            if value.endswith(' '+ch):
+                value = value[:-1-len(ch)]+ch
+    for ch in ('(', '['):
+        if ch+' ' in value and not punct:
+            print >> sys.stderr, 'ERROR: Translation for %r contains invalid punctuation (%s)' % (msgid, value)
+            punct = True
+            errors += 1
+
+        while ' '+ch+' ' in value:
+            value = value.replace(' '+ch+' ', ' '+ch)
+
+    return errors
+
+def main():
+    _, POT_DATA, _ = parsepo(os.path.join(ROOT, 'messages.pot'))
+
+    errors = 0
+    filenames = sys.argv[1:]
+    show_filenames = False
+    if not filenames:
+        filenames = glob.glob(os.path.join(ROOT, 'messages-*.po'))
+        show_filenames = True
+    for filename in filenames:
+        language = os.path.basename(filename)[9:-3]
+        if show_filenames:
+            print 'Checking %s (%s)' % (filename, language)
+        try:
+            parse_errors, data, untranslated = parsepo(filename)
+            if parse_errors:
+                errors += parse_errors
+        except Exception, e:
+            print >> sys.stderr, 'ERROR: Could not parse (%s)' % (e)
+            import traceback
+            traceback.print_exc(file=sys.stderr)
+            data = None
+
+        if data is None:
+            errors += 1
+            continue
+
+        file_errors = 0
+        for msgid, (msgstr, default) in POT_DATA.iteritems():
+            v = data.pop(msgid, None)
+            if v is None or not v[0]:
+                print >> sys.stderr, 'WARNING: Missing translation for %r' % (msgid)
+                continue
+
+            file_errors += check_translation(msgid, msgstr, default, v[0], language) or 0
+
+        if show_filenames:
+            print 'Found %d errors in %s' % (file_errors, filename)
+
+        print
+        errors += file_errors
+
+    if errors:
+        print >> sys.stderr, 'Found %d total errors' % (errors)
+        return 1
+
+    return 0
+
+if __name__ == '__main__':
+    import locale
+    locale.setlocale(locale.LC_ALL, 'en_US.UTF-8')
+    sys.exit(main())
diff --git a/src/i18n/messages-de.po b/src/i18n/messages-de.po
index 6841815a..3c9f06ac 100644
--- a/src/i18n/messages-de.po
+++ b/src/i18n/messages-de.po
@@ -101,10 +101,10 @@ msgid "Clear chat"
 msgstr "Chat löschen"
 
 msgid "is typing..."
-msgstr " schreibt gerade..."
+msgstr "schreibt gerade..."
 
 msgid "has stopped typing..."
-msgstr " schreibt nicht mehr..."
+msgstr "schreibt nicht mehr..."
 
 msgid "Type here to chat..."
 msgstr "Nachricht hier eingeben..."
@@ -366,7 +366,7 @@ msgid "Default room"
 msgstr "Standard Raum"
 
 msgid "Set alternative room to join at start."
-msgstr " Raum wird beim Start automatisch betreten."
+msgstr "Raum wird beim Start automatisch betreten."
 
 msgid "Notifications"
 msgstr "Benachrichtigungen"
@@ -645,7 +645,7 @@ msgstr "Kontakte"
 
 msgid "Restart required to apply updates. Click ok to restart now."
 msgstr ""
-"Es stehen Updates zur Verfügung. Klicken Sie Ok um die Anwendung  neu zu "
+"Es stehen Updates zur Verfügung. Klicken Sie Ok um die Anwendung neu zu "
 "starten."
 
 msgid "Failed to access camera/microphone."
diff --git a/src/i18n/messages-ja.po b/src/i18n/messages-ja.po
index dbb13ef5..aa588361 100644
--- a/src/i18n/messages-ja.po
+++ b/src/i18n/messages-ja.po
@@ -583,10 +583,10 @@ msgid "Peer to peer chat is now off."
 msgstr "ピア・ツー・ピア・チャットがオフです."
 
 msgid " is now offline."
-msgstr "は今オフラインです"
+msgstr " は今オフラインです"
 
 msgid " is now online."
-msgstr "は今オンラインです"
+msgstr " は今オンラインです"
 
 msgid "You share file:"
 msgstr "あなたの共有ファイル:"
@@ -652,21 +652,21 @@ msgid "User hung up because of error."
 msgstr "エラーのため切断しました."
 
 msgid " is busy. Try again later."
-msgstr "は話中です.後で掛けなおしてください."
+msgstr " は話中です.後で掛けなおしてください."
 
 msgid " rejected your call."
-msgstr "着信拒否されました."
+msgstr " 着信拒否されました."
 
 msgid " does not pick up."
-msgstr "は電話にでません."
+msgstr " は電話にでません."
 
 #, fuzzy
 msgid " tried to call you"
-msgstr "は電話しようとしました."
+msgstr " は電話しようとしました."
 
 #, fuzzy
 msgid " called you"
-msgstr "から電話がありました."
+msgstr " から電話がありました."
 
 #, fuzzy
 msgid "Your browser is not supported. Please upgrade to a current version."
diff --git a/src/i18n/messages-ko.po b/src/i18n/messages-ko.po
index 9b91ce52..2b3dec8c 100644
--- a/src/i18n/messages-ko.po
+++ b/src/i18n/messages-ko.po
@@ -583,10 +583,10 @@ msgid "Peer to peer chat is now off."
 msgstr "일대일 대화 꺼짐"
 
 msgid " is now offline."
-msgstr "현재 오프라인 상태"
+msgstr " 현재 오프라인 상태"
 
 msgid " is now online."
-msgstr "현재 온라인 상태"
+msgstr " 현재 온라인 상태"
 
 msgid "You share file:"
 msgstr "공유 화일:"
@@ -652,21 +652,21 @@ msgid "User hung up because of error."
 msgstr "오류로 인해 사용자 끊어짐"
 
 msgid " is busy. Try again later."
-msgstr "통화중. 다시 시도 하세요."
+msgstr " 통화중. 다시 시도 하세요."
 
 msgid " rejected your call."
-msgstr "전화가 거부 되었습니다."
+msgstr " 전화가 거부 되었습니다."
 
 msgid " does not pick up."
-msgstr "전화를 받지 않습니다."
+msgstr " 전화를 받지 않습니다."
 
 #, fuzzy
 msgid " tried to call you"
-msgstr "연결을 시도 중입니다"
+msgstr " 연결을 시도 중입니다"
 
 #, fuzzy
 msgid " called you"
-msgstr "전화 드렸습니다."
+msgstr " 전화 드렸습니다."
 
 #, fuzzy
 msgid "Your browser is not supported. Please upgrade to a current version."
diff --git a/src/i18n/messages-ru.po b/src/i18n/messages-ru.po
index d364c2a1..f0cabd1f 100644
--- a/src/i18n/messages-ru.po
+++ b/src/i18n/messages-ru.po
@@ -109,7 +109,7 @@ msgid "has stopped typing..."
 msgstr "перестал печатать..."
 
 msgid "Type here to chat..."
-msgstr "Введите здесь сообщения"
+msgstr "Введите здесь сообщения..."
 
 msgid "Send"
 msgstr "Отправить"
@@ -244,13 +244,13 @@ msgid "Screen sharing options"
 msgstr "Парамеры совместного использования экрана"
 
 msgid "Fit screen."
-msgstr "Разместить в экран"
+msgstr "Разместить в экран."
 
 msgid "Share screen"
 msgstr "Поделиться экраном"
 
 msgid "Please select what to share."
-msgstr "Пожалуйста выберите чем поделиться"
+msgstr "Пожалуйста выберите чем поделиться."
 
 msgid "Screen"
 msgstr "Экран"
@@ -359,7 +359,7 @@ msgid "Language"
 msgstr "Язык"
 
 msgid "Language changes become active on reload."
-msgstr "Изменение язака становится активным при перезагрузке"
+msgstr "Изменение язака становится активным при перезагрузке."
 
 msgid "Default room"
 msgstr "Комната по умолчанию"
@@ -589,10 +589,10 @@ msgid "YouTube video to share"
 msgstr "Видео YouTube, чтобы поделиться"
 
 msgid "Peer to peer chat active."
-msgstr "Пиринговый чат активен"
+msgstr "Пиринговый чат активен."
 
 msgid "Peer to peer chat is now off."
-msgstr "Пиринговый чат теперь выключена"
+msgstr "Пиринговый чат теперь выключена."
 
 msgid " is now offline."
 msgstr " вышел."