diff --git a/project/build.scala b/project/build.scala
index 61db306..d9bc7b0 100644
--- a/project/build.scala
+++ b/project/build.scala
@@ -32,7 +32,7 @@
         "org.scalatra" %% "scalatra-specs2" % ScalatraVersion % "test",
         "org.scalatra" %% "scalatra-json" % ScalatraVersion,
         "org.json4s" %% "json4s-jackson" % "3.2.5",
-        "jp.sf.amateras" %% "scalatra-forms" % "0.0.2",
+        "jp.sf.amateras" %% "scalatra-forms" % "0.0.4",
         "commons-io" % "commons-io" % "2.4",
         "org.pegdown" % "pegdown" % "1.4.1",
         "org.apache.commons" % "commons-compress" % "1.5",
diff --git a/src/main/scala/app/ControllerBase.scala b/src/main/scala/app/ControllerBase.scala
index a3406cc..bc71e11 100644
--- a/src/main/scala/app/ControllerBase.scala
+++ b/src/main/scala/app/ControllerBase.scala
@@ -15,12 +15,13 @@
 import javax.servlet.http.{HttpServletResponse, HttpSession, HttpServletRequest}
 import java.text.SimpleDateFormat
 import javax.servlet.{FilterChain, ServletResponse, ServletRequest}
+import org.scalatra.i18n._
 
 /**
  * Provides generic features for controller implementations.
  */
 abstract class ControllerBase extends ScalatraFilter
-  with ClientSideValidationFormSupport with JacksonJsonSupport with Validations {
+  with ClientSideValidationFormSupport with JacksonJsonSupport with I18nSupport with Validations {
 
   implicit val jsonFormats = DefaultFormats
 
@@ -169,12 +170,12 @@
     }
 
   protected def uniqueUserName: Constraint = new Constraint(){
-    override def validate(name: String, value: String): Option[String] =
+    override def validate(name: String, value: String, messages: Messages): Option[String] =
       getAccountByUserName(value).map { _ => "User already exists." }
   }
 
   protected def uniqueMailAddress(paramName: String = ""): Constraint = new Constraint(){
-    override def validate(name: String, value: String, params: Map[String, String]): Option[String] =
+    override def validate(name: String, value: String, params: Map[String, String], messages: Messages): Option[String] =
       getAccountByMailAddress(value)
         .filter { x => if(paramName.isEmpty) true else Some(x.userName) != params.get(paramName) }
         .map    { _ => "Mail address is already registered." }
diff --git a/src/main/scala/app/CreateRepositoryController.scala b/src/main/scala/app/CreateRepositoryController.scala
index c596b8c..67083aa 100644
--- a/src/main/scala/app/CreateRepositoryController.scala
+++ b/src/main/scala/app/CreateRepositoryController.scala
@@ -4,12 +4,11 @@
 import util.ControlUtil._
 import util._
 import service._
-import java.io.File
 import org.eclipse.jgit.api.Git
-import org.apache.commons.io._
 import jp.sf.amateras.scalatra.forms._
-import org.eclipse.jgit.lib.{FileMode, Constants, PersonIdent}
+import org.eclipse.jgit.lib.{FileMode, Constants}
 import org.eclipse.jgit.dircache.DirCache
+import org.scalatra.i18n.Messages
 
 class CreateRepositoryController extends CreateRepositoryControllerBase
   with RepositoryService with AccountService with WikiService with LabelsService with ActivityService
@@ -175,7 +174,7 @@
   }
 
   private def existsAccount: Constraint = new Constraint(){
-    override def validate(name: String, value: String): Option[String] =
+    override def validate(name: String, value: String, messages: Messages): Option[String] =
       if(getAccountByUserName(value).isEmpty) Some("User or group does not exist.") else None
   }
 
@@ -183,7 +182,7 @@
    * Duplicate check for the repository name.
    */
   private def unique: Constraint = new Constraint(){
-    override def validate(name: String, value: String, params: Map[String, String]): Option[String] =
+    override def validate(name: String, value: String, params: Map[String, String], messages: Messages): Option[String] =
       params.get("owner").flatMap { userName =>
         getRepositoryNamesOfUser(userName).find(_ == value).map(_ => "Repository already exists.")
       }
diff --git a/src/main/scala/app/LabelsController.scala b/src/main/scala/app/LabelsController.scala
index 1366c4c..2a222bd 100644
--- a/src/main/scala/app/LabelsController.scala
+++ b/src/main/scala/app/LabelsController.scala
@@ -3,6 +3,7 @@
 import jp.sf.amateras.scalatra.forms._
 import service._
 import util.CollaboratorsAuthenticator
+import org.scalatra.i18n.Messages
 
 class LabelsController extends LabelsControllerBase
   with LabelsService with RepositoryService with AccountService with CollaboratorsAuthenticator
@@ -51,7 +52,7 @@
    * Constraint for the identifier such as user name, repository name or page name.
    */
   private def labelName: Constraint = new Constraint(){
-    override def validate(name: String, value: String): Option[String] =
+    override def validate(name: String, value: String, messages: Messages): Option[String] =
       if(!value.matches("^[^,]+$")){
         Some(s"${name} contains invalid character.")
       } else if(value.startsWith("_") || value.startsWith("-")){
diff --git a/src/main/scala/app/RepositorySettingsController.scala b/src/main/scala/app/RepositorySettingsController.scala
index e6c1c91..05987d5 100644
--- a/src/main/scala/app/RepositorySettingsController.scala
+++ b/src/main/scala/app/RepositorySettingsController.scala
@@ -6,6 +6,7 @@
 import jp.sf.amateras.scalatra.forms._
 import org.apache.commons.io.FileUtils
 import org.scalatra.FlashMapSupport
+import org.scalatra.i18n.Messages
 import service.WebHookService.WebHookPayload
 import util.JGitUtil.CommitInfo
 import util.ControlUtil._
@@ -179,7 +180,7 @@
    * Provides duplication check for web hook url.
    */
   private def webHook: Constraint = new Constraint(){
-    override def validate(name: String, value: String): Option[String] =
+    override def validate(name: String, value: String, messages: Messages): Option[String] =
       getWebHookURLs(params("owner"), params("repository")).map(_.url).find(_ == value).map(_ => "URL had been registered already.")
   }
 
@@ -187,7 +188,7 @@
    * Provides Constraint to validate the collaborator name.
    */
   private def collaborator: Constraint = new Constraint(){
-    override def validate(name: String, value: String): Option[String] =
+    override def validate(name: String, value: String, messages: Messages): Option[String] =
       getAccountByUserName(value) match {
         case None => Some("User does not exist.")
         case Some(x) if(x.isGroupAccount)
diff --git a/src/main/scala/app/WikiController.scala b/src/main/scala/app/WikiController.scala
index e7eaf23..aaa88a8 100644
--- a/src/main/scala/app/WikiController.scala
+++ b/src/main/scala/app/WikiController.scala
@@ -7,8 +7,9 @@
 import jp.sf.amateras.scalatra.forms._
 import org.eclipse.jgit.api.Git
 import org.scalatra.FlashMapSupport
-import service.WikiService.WikiPageInfo
+import org.scalatra.i18n.Messages
 import scala.Some
+import java.util.ResourceBundle
 
 class WikiController extends WikiControllerBase 
   with WikiService with RepositoryService with AccountService with ActivityService
@@ -170,12 +171,12 @@
   })
 
   private def unique: Constraint = new Constraint(){
-    override def validate(name: String, value: String, params: Map[String, String]): Option[String] =
+    override def validate(name: String, value: String, params: Map[String, String], messages: Messages): Option[String] =
       getWikiPageList(params("owner"), params("repository")).find(_ == value).map(_ => "Page already exists.")
   }
 
   private def pagename: Constraint = new Constraint(){
-    override def validate(name: String, value: String): Option[String] =
+    override def validate(name: String, value: String, messages: Messages): Option[String] =
       if(value.exists("\\/:*?\"<>|".contains(_))){
         Some(s"${name} contains invalid character.")
       } else if(value.startsWith("_") || value.startsWith("-")){
@@ -186,7 +187,7 @@
   }
 
   private def conflictForNew: Constraint = new Constraint(){
-    override def validate(name: String, value: String): Option[String] = {
+    override def validate(name: String, value: String, messages: Messages): Option[String] = {
       optionIf(targetWikiPage.nonEmpty){
         Some("Someone has created the wiki since you started. Please reload this page and re-apply your changes.")
       }
@@ -194,7 +195,7 @@
   }
 
   private def conflictForEdit: Constraint = new Constraint(){
-    override def validate(name: String, value: String): Option[String] = {
+    override def validate(name: String, value: String, messages: Messages): Option[String] = {
       optionIf(targetWikiPage.map(_.id != params("id")).getOrElse(false)){
         Some("Someone has edited the wiki since you started. Please reload this page and re-apply your changes.")
       }
diff --git a/src/main/scala/util/Validations.scala b/src/main/scala/util/Validations.scala
index 255689e..ebb0072 100644
--- a/src/main/scala/util/Validations.scala
+++ b/src/main/scala/util/Validations.scala
@@ -1,6 +1,7 @@
 package util
 
 import jp.sf.amateras.scalatra.forms._
+import org.scalatra.i18n.Messages
 
 trait Validations {
 
@@ -8,7 +9,7 @@
    * Constraint for the identifier such as user name, repository name or page name.
    */
   def identifier: Constraint = new Constraint(){
-    override def validate(name: String, value: String): Option[String] =
+    override def validate(name: String, value: String, messages: Messages): Option[String] =
       if(!value.matches("^[a-zA-Z0-9\\-_.]+$")){
         Some(s"${name} contains invalid character.")
       } else if(value.startsWith("_") || value.startsWith("-")){
@@ -25,7 +26,7 @@
    */
   def date(constraints: Constraint*): SingleValueType[java.util.Date] =
     new SingleValueType[java.util.Date]((pattern("\\d{4}-\\d{2}-\\d{2}") +: constraints): _*){
-      def convert(value: String): java.util.Date = new java.text.SimpleDateFormat("yyyy-MM-dd").parse(value)
+      def convert(value: String, messages: Messages): java.util.Date = new java.text.SimpleDateFormat("yyyy-MM-dd").parse(value)
     }
 
 }