--- loncom/interface/lonnavmaps.pm	2009/12/03 17:50:42	1.440
+++ loncom/interface/lonnavmaps.pm	2010/01/07 12:42:43	1.442
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Navigate Maps Handler
 #
-# $Id: lonnavmaps.pm,v 1.440 2009/12/03 17:50:42 bisitz Exp $
+# $Id: lonnavmaps.pm,v 1.442 2010/01/07 12:42:43 wenzelju Exp $
 
 #
 # Copyright Michigan State University Board of Trustees
@@ -1037,7 +1037,7 @@ sub render_communication_status {
     my $location=&Apache::loncommon::lonhttpdurl("/adm/lonMisc");
     if ($resource->hasDiscussion()) {
         $discussionHTML = $linkopen .
-            '<img alt="'.&mt('New Discussion').'" src="'.$location.'/chat.gif" />' .
+            '<img alt="'.&mt('New Discussion').'" src="'.$location.'/chat.gif" title="'.&mt('New Discussion').'"/>' .
             $linkclose;
     }
     
@@ -1047,7 +1047,7 @@ sub render_communication_status {
             if ($msgid) {
                 $feedbackHTML .= '&nbsp;<a '.$target.' href="/adm/email?display='
                     . &escape($msgid) . '">'
-                    . '<img alt="'.&mt('New E-mail').'" src="'.$location.'/feedback.gif" /></a>';
+                    . '<img alt="'.&mt('New E-mail').'" src="'.$location.'/feedback.gif" title="'.&mt('New E-mail').'"/></a>';
             }
         }
     }
@@ -1061,7 +1061,7 @@ sub render_communication_status {
                 $errorcount++;
                 $errorHTML .= '&nbsp;<a '.$target.' href="/adm/email?display='
                     . &escape($msgid) . '">'
-                    . '<img alt="'.&mt('New Error').'" src="'.$location.'/bomb.gif" /></a>';
+                    . '<img alt="'.&mt('New Error').'" src="'.$location.'/bomb.gif" title="'.&mt('New Error').'"/></a>';
             }
         }
     }
@@ -3532,7 +3532,11 @@ sub navHash {
     my $self = shift;
     my $param = shift;
     my $id = shift;
-    return $self->{NAV_MAP}->navhash($param . ($id?$self->{ID}:""));
+    my $arg = $param . ($id?$self->{ID}:"");
+    if (defined($arg)) {
+        return $self->{NAV_MAP}->navhash($arg);
+    }
+    return;
 }
 
 =pod