diff --git a/gen/mixins/ToolMixin.py b/gen/mixins/ToolMixin.py
index 3999346..21bcfb8 100644
--- a/gen/mixins/ToolMixin.py
+++ b/gen/mixins/ToolMixin.py
@@ -1136,13 +1136,22 @@ class ToolMixin(BaseMixin):
     def manageError(self, error):
         '''Manages an error.'''
         tb = sys.exc_info()
-        from zExceptions.ExceptionFormatter import format_exception
-        htmlMessage = format_exception(tb[0], tb[1], tb[2], as_html=1)
-        textMessage = format_exception(tb[0], tb[1], tb[2], as_html=0)
-        self.log(''.join(textMessage).strip(), type='error')
-        return '<table class="main" align="center" cellpadding="0"><tr>' \
-               '<td style="padding: 1em 1em 1em 1em">An error occurred. %s' \
-               '</td></tr></table>' % '\n'.join(htmlMessage)
+        if error.type.__name__ == 'Unauthorized':
+            siteUrl = self.getSiteUrl()
+            htmlMessage = '<a href="%s"><img src="%s/ui/home.gif"/></a>' \
+                          'You are not allowed to access this page.' % \
+                          (siteUrl, siteUrl)
+            userId = self.appy().user.getId() or 'system|anon'
+            textMessage = 'Unauthorized for %s @%s.' % \
+                          (userId, self.REQUEST.get('PATH_INFO'))
+        else:
+            from zExceptions.ExceptionFormatter import format_exception
+            htmlMessage = format_exception(tb[0], tb[1], tb[2], as_html=1)
+            htmlMessage = '\n'.join(htmlMessage)
+            textMessage = format_exception(tb[0], tb[1], tb[2], as_html=0)
+            textMessage = ''.join(textMessage).strip()
+        self.log(textMessage, type='error')
+        return '<div class="error" align="center">%s</div>' % htmlMessage
 
     def getMainPages(self):
         '''Returns the main pages.'''
diff --git a/gen/ui/appy.css b/gen/ui/appy.css
index 08b570d..fc9a1e7 100644
--- a/gen/ui/appy.css
+++ b/gen/ui/appy.css
@@ -146,3 +146,4 @@ img { border: 0; vertical-align: middle }
 .homeTable td { padding: 10px 5px 10px 10px }
 .homeTable th { padding-top: 5px; font-size: 105% }
 .first { margin-top: 0px }
+.error { margin: 5px }
diff --git a/gen/ui/page.pt b/gen/ui/page.pt
index 860437d..d4ce6fa 100644
--- a/gen/ui/page.pt
+++ b/gen/ui/page.pt
@@ -118,8 +118,10 @@
       </td>
       <td tal:condition="not: isDataChange"
           tal:content="python: _(contextObj.getWorkflowLabel(event['action']))"/>
-      <td tal:define="actorId python:event.get('actor')"
-          tal:content="python: tool.getUserName(actorId)"/>
+      <td tal:define="actorId python:event.get('actor')">
+       <span tal:condition="not: actorId" tal:replace="python: '?'"/>
+       <span tal:condition="actorId" tal:content="python: tool.getUserName(actorId)"></span>
+      </td>
       <td tal:content="python: tool.formatDate(event['time'], withHour=True)"/>
       <td tal:condition="not: isDataChange">
         <tal:c condition="rhComments"