diff --git a/src/IDF/Form/IssueCreate.php b/src/IDF/Form/IssueCreate.php
index 5fcaed3..cd86193 100644
--- a/src/IDF/Form/IssueCreate.php
+++ b/src/IDF/Form/IssueCreate.php
@@ -114,7 +114,7 @@ class IDF_Form_IssueCreate extends Pluf_Form
                                             ));
             $this->fields['due_dtime'] = new Pluf_Form_Field_Datetime(
                                           array('required' => false,
-                                                'label' => __('Due Date'),
+                                                'label' => __('Due date'),
                                                 'initial' => '',
                                                 'widget_attrs' => array('size' => 15,),
                                               ));
diff --git a/src/IDF/Form/IssueUpdate.php b/src/IDF/Form/IssueUpdate.php
index e18fa1f..302c0a4 100644
--- a/src/IDF/Form/IssueUpdate.php
+++ b/src/IDF/Form/IssueUpdate.php
@@ -105,7 +105,7 @@ class IDF_Form_IssueUpdate  extends IDF_Form_IssueCreate
                                             ));
             $this->fields['due_dtime'] = new Pluf_Form_Field_Datetime(
                                 array('required' => false,
-                                    'label' => __('Due Date'),
+                                    'label' => __('Due date'),
                                     'initial' => $this->issue->due_dtime,
                                     'widget_attrs' => array('size' => 15,),
                                     ));
diff --git a/src/IDF/Issue.php b/src/IDF/Issue.php
index 00eece9..3fb94f3 100644
--- a/src/IDF/Issue.php
+++ b/src/IDF/Issue.php
@@ -95,6 +95,7 @@ class IDF_Issue extends Pluf_Model
                             array(
                                   'type' => 'Pluf_DB_Field_Datetime',
                                   'blank' => true,
+                                  'is_null' => true,
                                   'verbose' => __('due date'),
                                   ),
                             'status' =>
diff --git a/src/IDF/IssueComment.php b/src/IDF/IssueComment.php
index a418438..6ba45c1 100644
--- a/src/IDF/IssueComment.php
+++ b/src/IDF/IssueComment.php
@@ -154,7 +154,7 @@ class IDF_IssueComment extends Pluf_Model
                 case 'ow':
                     $out .= __('Owner:'); break;
                 case 'du':
-                    $out .= __('Due Date:'); break;
+                    $out .= __('Due date:'); break;
                 case 'lb':
                     $out .= __('Labels:'); break;
                 case 'rel':
diff --git a/src/IDF/templates/idf/issues/view.html b/src/IDF/templates/idf/issues/view.html
index 1943638..47002ca 100644
--- a/src/IDF/templates/idf/issues/view.html
+++ b/src/IDF/templates/idf/issues/view.html
@@ -40,7 +40,7 @@
 {if $i> 0 and $c.changedIssue()}
 <div class="issue-changes">
 {foreach $c.changes as $w => $v}
-<strong>{if $w == 'su'}{trans 'Summary:'}{/if}{if $w == 'st'}{trans 'Status:'}{/if}{if $w == 'ow'}{trans 'Owner:'}{/if}{if $w == 'du'}{trans 'Due Date:'}{/if}{if $w == 'lb'}{trans 'Labels:'}{/if}{if $w == 'rel'}{trans 'Relations:'}{/if}</strong>
+<strong>{if $w == 'su'}{trans 'Summary:'}{/if}{if $w == 'st'}{trans 'Status:'}{/if}{if $w == 'ow'}{trans 'Owner:'}{/if}{if $w == 'du'}{trans 'Due date:'}{/if}{if $w == 'lb'}{trans 'Labels:'}{/if}{if $w == 'rel'}{trans 'Relations:'}{/if}</strong>
 {if $w == 'lb' or $w == 'rel'}
   {foreach $v as $t => $ls}
     {foreach $ls as $l}