diff --git a/src/main/scala/app/AccountController.scala b/src/main/scala/app/AccountController.scala
index 0b21de4..d8e6362 100644
--- a/src/main/scala/app/AccountController.scala
+++ b/src/main/scala/app/AccountController.scala
@@ -70,7 +70,7 @@
     val userName = params("userName")
     getAccountByUserName(userName).map { account =>
       updateAccount(account.copy(
-        password    = form.password.map(encrypt).getOrElse(account.password),
+        password    = form.password.map(sha1).getOrElse(account.password),
         mailAddress = form.mailAddress,
         url         = form.url))
 
@@ -93,7 +93,7 @@
 
   post("/register", newForm){ form =>
     if(loadSystemSettings().allowAccountRegistration){
-      createAccount(form.userName, encrypt(form.password), form.mailAddress, false, form.url)
+      createAccount(form.userName, sha1(form.password), form.mailAddress, false, form.url)
       updateImage(form.userName, form.fileId, false)
       redirect("/signin")
     } else NotFound
diff --git a/src/main/scala/app/ControllerBase.scala b/src/main/scala/app/ControllerBase.scala
index 7d88da8..b338f36 100644
--- a/src/main/scala/app/ControllerBase.scala
+++ b/src/main/scala/app/ControllerBase.scala
@@ -95,7 +95,23 @@
 /**
  * Context object for the current request.
  */
-case class Context(path: String, loginAccount: Option[Account], currentUrl: String, request: HttpServletRequest)
+case class Context(path: String, loginAccount: Option[Account], currentUrl: String, request: HttpServletRequest){
+
+  /**
+   * Get object from cache.
+   *
+   * If object has not been cached with the specified key then retrieves by given action.
+   * Cached object are available during a request.
+   */
+  def cache[A](key: String)(action: => A): A = {
+    Option(request.getAttribute("cache." + key).asInstanceOf[A]).getOrElse {
+      val newObject = action
+      request.setAttribute("cache." + key, newObject)
+      newObject
+    }
+  }
+
+}
 
 /**
  * Base trait for controllers which manages account information.
diff --git a/src/main/scala/app/RepositoryViewerController.scala b/src/main/scala/app/RepositoryViewerController.scala
index 2d1b6a3..4ba43cb 100644
--- a/src/main/scala/app/RepositoryViewerController.scala
+++ b/src/main/scala/app/RepositoryViewerController.scala
@@ -213,11 +213,17 @@
     if(repository.commitCount == 0){
       repo.html.guide(repository)
     } else {
-      val revision = if(revstr.isEmpty) repository.repository.defaultBranch else revstr
-
       JGitUtil.withGit(getRepositoryDir(repository.owner, repository.name)){ git =>
-        // get latest commit
-        val revCommit = JGitUtil.getRevCommitFromId(git, git.getRepository.resolve(revision))
+        // get specified commit
+        val (revCommit, revision) = try {
+          val revision = if(revstr.isEmpty) repository.repository.defaultBranch else revstr
+          (JGitUtil.getRevCommitFromId(git, git.getRepository.resolve(revision)), revision)
+        } catch {
+          case e: NullPointerException => {
+            val revision = repository.branchList.head
+            (JGitUtil.getRevCommitFromId(git, git.getRepository.resolve(revision)), revision)
+          }
+        }
         // get files
         val files = JGitUtil.getFileList(git, revision, path)
         // process README.md
@@ -225,20 +231,10 @@
           new String(JGitUtil.getContent(Git.open(getRepositoryDir(repository.owner, repository.name)), file.id, true).get, "UTF-8")
         }
 
-        repo.html.files(
-          // current branch
-          revision,
-          // repository
-          repository,
-          // current path
-          if(path == ".") Nil else path.split("/").toList,
-          // latest commit
-          new JGitUtil.CommitInfo(revCommit),
-          // file list
-          files,
-          // readme
-          readme
-        )
+        repo.html.files(revision, repository,
+          if(path == ".") Nil else path.split("/").toList, // current path
+          new JGitUtil.CommitInfo(revCommit), // latest commit
+          files, readme)
       }
     }
   }
diff --git a/src/main/scala/app/SignInController.scala b/src/main/scala/app/SignInController.scala
index 3e00963..becc3b2 100644
--- a/src/main/scala/app/SignInController.scala
+++ b/src/main/scala/app/SignInController.scala
@@ -25,7 +25,7 @@
 
   post("/signin", form){ form =>
     val account = getAccountByUserName(form.userName)
-    if(account.isEmpty || account.get.password != encrypt(form.password)){
+    if(account.isEmpty || account.get.password != sha1(form.password)){
       redirect("/signin")
     } else {
       session.setAttribute("LOGIN_ACCOUNT", account.get)
diff --git a/src/main/scala/app/UserManagementController.scala b/src/main/scala/app/UserManagementController.scala
index d21308a..e5673d4 100644
--- a/src/main/scala/app/UserManagementController.scala
+++ b/src/main/scala/app/UserManagementController.scala
@@ -47,7 +47,7 @@
   })
   
   post("/admin/users/_new", newForm)(adminOnly { form =>
-    createAccount(form.userName, encrypt(form.password), form.mailAddress, form.isAdmin, form.url)
+    createAccount(form.userName, sha1(form.password), form.mailAddress, form.isAdmin, form.url)
     updateImage(form.userName, form.fileId, false)
     redirect("/admin/users")
   })
@@ -61,7 +61,7 @@
     val userName = params("userName")
     getAccountByUserName(userName).map { account =>
       updateAccount(getAccountByUserName(userName).get.copy(
-        password     = form.password.map(encrypt).getOrElse(account.password),
+        password     = form.password.map(sha1).getOrElse(account.password),
         mailAddress  = form.mailAddress,
         isAdmin      = form.isAdmin,
         url          = form.url))
diff --git a/src/main/scala/servlet/BasicAuthenticationFilter.scala b/src/main/scala/servlet/BasicAuthenticationFilter.scala
index 1f6e8f7..a69c237 100644
--- a/src/main/scala/servlet/BasicAuthenticationFilter.scala
+++ b/src/main/scala/servlet/BasicAuthenticationFilter.scala
@@ -59,7 +59,7 @@
 
   private def isWritableUser(username: String, password: String, repository: RepositoryService.RepositoryInfo): Boolean = {
     getAccountByUserName(username).map { account =>
-      account.password == encrypt(password) && hasWritePermission(repository.owner, repository.name, Some(account))
+      account.password == sha1(password) && hasWritePermission(repository.owner, repository.name, Some(account))
     } getOrElse false
   }
   
diff --git a/src/main/scala/util/Implicits.scala b/src/main/scala/util/Implicits.scala
index 92f1d1d..1de9e24 100644
--- a/src/main/scala/util/Implicits.scala
+++ b/src/main/scala/util/Implicits.scala
@@ -7,8 +7,8 @@
  * Provides some usable implicit conversions.
  */
 object Implicits {
-  
-  implicit def extendsSeq[A](seq: Seq[A]) = new {
+
+  implicit class RichSeq[A](seq: Seq[A]) {
 
     def splitWith(condition: (A, A) => Boolean): Seq[Seq[A]] = split(seq)(condition)
 
@@ -26,7 +26,7 @@
   }
 
   // TODO Should this implicit conversion move to model.Functions?
-  implicit def extendsColumn(c1: Column[Boolean]) = new {
+  implicit class RichColumn(c1: Column[Boolean]){
     def &&(c2: => Column[Boolean], guard: => Boolean): Column[Boolean] = if(guard) c1 && c2 else c1
   }
 
diff --git a/src/main/scala/util/StringUtil.scala b/src/main/scala/util/StringUtil.scala
index bc478c7..9cce293 100644
--- a/src/main/scala/util/StringUtil.scala
+++ b/src/main/scala/util/StringUtil.scala
@@ -2,7 +2,7 @@
 
 object StringUtil {
 
-  def encrypt(value: String): String = {
+  def sha1(value: String): String = {
     val md = java.security.MessageDigest.getInstance("SHA-1")
     md.update(value.getBytes)
     md.digest.map(b => "%02x".format(b)).mkString
diff --git a/src/main/scala/view/helpers.scala b/src/main/scala/view/helpers.scala
index fdb3734..b12f644 100644
--- a/src/main/scala/view/helpers.scala
+++ b/src/main/scala/view/helpers.scala
@@ -75,16 +75,14 @@
       // convert commit id to link
       .replaceAll("(^|\\W)([a-f0-9]{40})(\\W|$)", "$1<a href=\"%s/%s/%s/commit/$2\">$2</a>$3").format(context.path, repository.owner, repository.name))
 
+
   /**
    * Returns &lt;img&gt; which displays the avatar icon.
    * Looks up Gravatar if avatar icon has not been configured in user settings.
    */
   def avatar(userName: String, size: Int, tooltip: Boolean = false)(implicit context: app.Context): Html = {
-    val account = Option(context.request.getAttribute("cache.account." + userName).asInstanceOf[model.Account]).orElse {
-      new AccountService {}.getAccountByUserName(userName).map { account =>
-        context.request.setAttribute("cache.account." + userName, account)
-        account
-      }
+    val account = context.cache(s"account.${userName}"){
+      new AccountService {}.getAccountByUserName(userName)
     }
     val src = account.collect { case account if(account.image.isEmpty) =>
       s"""http://www.gravatar.com/avatar/${StringUtil.md5(account.mailAddress)}?s=${size}"""
@@ -92,16 +90,16 @@
       s"""${context.path}/${userName}/_avatar"""
     }
     if(tooltip){
-      Html(s"""<img src=${src} class="avatar" style="width: ${size}px; height: ${size}:px" data-toggle="tooltip" title=${userName}/>""")
+      Html(s"""<img src=${src} class="avatar" style="width: ${size}px; height: ${size}px;" data-toggle="tooltip" title=${userName}/>""")
     } else {
-      Html(s"""<img src=${src} class="avatar" style="width: ${size}px; height: ${size}:px" />""")
+      Html(s"""<img src=${src} class="avatar" style="width: ${size}px; height: ${size}px;" />""")
     }
   }
 
   /**
    * Implicit conversion to add mkHtml() to Seq[Html].
    */
-  implicit def extendsHtmlSeq(seq: Seq[Html]) = new {
+  implicit class RichHtmlSeq(seq: Seq[Html]) {
     def mkHtml(separator: String) = Html(seq.mkString(separator))
     def mkHtml(separator: scala.xml.Elem) = Html(seq.mkString(separator.toString))
   }
diff --git a/src/main/twirl/issues/create.scala.html b/src/main/twirl/issues/create.scala.html
index cfa330a..68d8eff 100644
--- a/src/main/twirl/issues/create.scala.html
+++ b/src/main/twirl/issues/create.scala.html
@@ -11,10 +11,11 @@
   <form action="@url(repository)/issues/new" method="POST" validate="true">
   <div class="row-fluid">
     <div class="span9">
-      <div class="box">
+      <div class="issue-avatar-image">@avatar(loginAccount.get.userName, 48)</div>
+      <div class="box issue-box">
         <div class="box-content">
           <span id="error-title" class="error"></span>
-          <input type="text" name="title" value="" placeholder="Title" style="width: 650px;"/>
+          <input type="text" name="title" value="" placeholder="Title" style="width: 600px;"/>
           <div>
             <span id="label-assigned">No one is assigned</span>
             @if(hasWritePermission){
@@ -42,10 +43,12 @@
             </div>
           </div>
           <hr>
-          @helper.html.preview(repository, "", false, true, true, "width: 650px; height: 200px;")
+          @helper.html.preview(repository, "", false, true, true, "width: 600px; height: 200px;")
         </div>
       </div>
-      <input type="submit" class="btn btn-success" value="Submit new issue"/>
+      <div class="pull-right">
+        <input type="submit" class="btn btn-success" value="Submit new issue"/>
+      </div>
     </div>
     <div class="span3">
       @if(hasWritePermission){
diff --git a/src/main/twirl/issues/editcomment.scala.html b/src/main/twirl/issues/editcomment.scala.html
index f5b9354..683956a 100644
--- a/src/main/twirl/issues/editcomment.scala.html
+++ b/src/main/twirl/issues/editcomment.scala.html
@@ -1,7 +1,7 @@
 @(content: String, commentId: Int, owner: String, repository: String)(implicit context: app.Context)
 @import context._
 <span id="error-edit-content-@commentId" class="error"></span>
-<textarea style="width: 730px; height: 100px;" id="edit-content-@commentId">@content</textarea>
+<textarea style="width: 680px; height: 100px;" id="edit-content-@commentId">@content</textarea>
 <input type="button" class="btn btn-small" value="Update Comment"/>
 <span class="pull-right"><a class="btn btn-small btn-danger" href="#">Cancel</a></span>
 <script>
diff --git a/src/main/twirl/issues/editissue.scala.html b/src/main/twirl/issues/editissue.scala.html
index fadd50a..12d41b0 100644
--- a/src/main/twirl/issues/editissue.scala.html
+++ b/src/main/twirl/issues/editissue.scala.html
@@ -1,8 +1,8 @@
 @(title: String, content: Option[String], issueId: Int, owner: String, repository: String)(implicit context: app.Context)
 @import context._
 <span id="error-edit-title" class="error"></span>
-<input type="text" style="width: 730px;" id="edit-title" value="@title"/>
-<textarea style="width: 730px; height: 100px;" id="edit-content">@content.getOrElse("")</textarea>
+<input type="text" style="width: 680px;" id="edit-title" value="@title"/>
+<textarea style="width: 680px; height: 100px;" id="edit-content">@content.getOrElse("")</textarea>
 <input type="button" class="btn btn-small" value="Update Issue"/>
 <span class="pull-right"><a class="btn btn-small btn-danger" href="#">Cancel</a></span>
 <script>
diff --git a/src/main/twirl/issues/issue.scala.html b/src/main/twirl/issues/issue.scala.html
index 218c721..2e35ac3 100644
--- a/src/main/twirl/issues/issue.scala.html
+++ b/src/main/twirl/issues/issue.scala.html
@@ -17,7 +17,8 @@
   </ul>
   <div class="row-fluid">
     <div class="span10">
-      <div class="box">
+      <div class="issue-avatar-image">@avatar(issue.openedUserName, 48)</div>
+      <div class="box issue-box">
         <div class="box-content" style="padding: 0px;">
           <div class="issue-header">
             @if(hasWritePermission || loginAccount.map(_.userName == issue.openedUserName).getOrElse(false)){
@@ -68,6 +69,7 @@
         </div>
       </div>
       @comments.map { comment =>
+        <div class="issue-avatar-image">@avatar(comment.commentedUserName, 48)</div>
         <div class="box issue-comment-box" id="comment-@comment.commentId">
           <div class="box-header-small">
             <i class="icon-comment"></i>
@@ -97,16 +99,19 @@
       }
       @if(loginAccount.isDefined){
         <form action="@url(repository)/issue_comments/new" method="POST" validate="true">
-          <div class="box">
+          <div class="issue-avatar-image">@avatar(loginAccount.get.userName, 48)</div>
+          <div class="box issue-comment-box">
             <div class="box-content">
-              @helper.html.preview(repository, "", false, true, true, "width: 730px; height: 100px;")
+              @helper.html.preview(repository, "", false, true, true, "width: 680px; height: 100px;")
             </div>
           </div>
-          <input type="hidden" name="issueId" value="@issue.issueId"/>
-          <input type="submit" class="btn btn-success" value="Comment"/>
-          @if(hasWritePermission || issue.openedUserName == loginAccount.get.userName){
-            <input type="submit" class="btn" value="@{if(issue.closed) "Reopen" else "Close"}" id="action"/>
-          }
+          <div class="pull-right">
+            <input type="hidden" name="issueId" value="@issue.issueId"/>
+            <input type="submit" class="btn btn-success" value="Comment"/>
+            @if(hasWritePermission || issue.openedUserName == loginAccount.get.userName){
+              <input type="submit" class="btn" value="@{if(issue.closed) "Reopen" else "Close"}" id="action"/>
+            }
+          </div>
         </form>
       }
     </div>
diff --git a/src/main/twirl/repo/tab.scala.html b/src/main/twirl/repo/tab.scala.html
index 077a816..8a1d859 100644
--- a/src/main/twirl/repo/tab.scala.html
+++ b/src/main/twirl/repo/tab.scala.html
@@ -1,15 +1,21 @@
-@(id: String, repository: service.RepositoryService.RepositoryInfo, active: String)(implicit context: app.Context)
+@(id: String, repository: service.RepositoryService.RepositoryInfo, active: String,
+  hideBranchPulldown: Boolean = false)(implicit context: app.Context)
 @import context._
 @import view.helpers._
 <ul class="nav nav-tabs">
+  @if(!hideBranchPulldown){
   <li>
     <div class="btn-group" style="margin-right: 20px;">
       <button class="btn dropdown-toggle" data-toggle="dropdown">
         @if(id.length == 40){
           tree: <strong>@id.substring(0, 10)</strong>
-        } else {
+        }
+        @if(repository.branchList.contains(id)){
           branch: <strong>@id</strong>
         }
+        @if(repository.tags.exists(_.name == id)){
+          tag: <strong>@id</strong>
+        }
         <span class="caret"></span>
       </button>
       <ul class="dropdown-menu">
@@ -19,6 +25,7 @@
       </ul>
     </div>
   </li>
+  }
   <li@if(active=="files"){ class="active"}><a href="@url(repository)/tree/@id">Files</a></li>
   <li@if(active=="commits"){ class="active"}><a href="@url(repository)/commits/@id">Commits</a></li>
   <li@if(active=="tags"){ class="active"}><a href="@url(repository)/tags">Tags@if(repository.tags.length > 0){ <span class="badge">@repository.tags.length</span>}</a></li>
diff --git a/src/main/twirl/repo/tags.scala.html b/src/main/twirl/repo/tags.scala.html
index 76f74af..c8a4331 100644
--- a/src/main/twirl/repo/tags.scala.html
+++ b/src/main/twirl/repo/tags.scala.html
@@ -3,7 +3,7 @@
 @import view.helpers._
 @html.main(repository.owner + "/" + repository.name) {
   @html.header("code", repository)
-  @tab("master", repository, "tags") @* TODO DON'T display branch pulldown *@
+  @tab(repository.repository.defaultBranch, repository, "tags", true)
   <h1>Tags</h1>
   <table class="table table-bordered">
     <tr>
diff --git a/src/main/webapp/WEB-INF/web.xml b/src/main/webapp/WEB-INF/web.xml
index 101dcd9..1f509d5 100644
--- a/src/main/webapp/WEB-INF/web.xml
+++ b/src/main/webapp/WEB-INF/web.xml
@@ -8,7 +8,7 @@
   <!-- Session configuration -->
   <!-- ===================================================================== -->
   <listener>
-    <listener-class>servlet.SessionCleanipListener</listener-class>
+    <listener-class>servlet.SessionCleanupListener</listener-class>
   </listener>
 
   <!-- ===================================================================== -->
diff --git a/src/main/webapp/assets/common/css/gitbucket.css b/src/main/webapp/assets/common/css/gitbucket.css
index 0aacee7..580116d 100644
--- a/src/main/webapp/assets/common/css/gitbucket.css
+++ b/src/main/webapp/assets/common/css/gitbucket.css
@@ -502,9 +502,18 @@
   padding: 0px;
 }
 
+div.issue-avatar-image {
+  float: left;
+}
+
+div.issue-box {
+  margin-bottom: 15px;
+  margin-left: 50px;
+}
+
 div.issue-comment-box {
   margin-bottom: 15px;
-  margin-top: 25px;
+  margin-left: 50px;
 }
 
 div.issue-comment-action {