diff --git a/plugins/archive/archive.php b/plugins/archive/archive.php
index 7bfb985e4..fc9432f43 100644
--- a/plugins/archive/archive.php
+++ b/plugins/archive/archive.php
@@ -188,6 +188,12 @@ class archive extends rcube_plugin
                             . $delimiter . $rcmail->format_date($message->timestamp, 'm');
                         break;
 
+                    case 'thunderbirdmonth':
+                        $subfolder = $rcmail->format_date($message->timestamp, 'Y')
+                            . $delimiter . $rcmail->format_date($message->timestamp, 'Y')
+                            . '-' . $rcmail->format_date($message->timestamp, 'm');
+                        break;
+
                     case 'sender':
                         $from = $message->get('from');
                         preg_match('/[\b<](.+@.+)[\b>]/i', $from, $m);
@@ -410,6 +416,7 @@ class archive extends rcube_plugin
             $archive_type->add($this->gettext('none'), '');
             $archive_type->add($this->gettext('archivetypeyear'), 'year');
             $archive_type->add($this->gettext('archivetypemonth'), 'month');
+            $archive_type->add($this->gettext('archivetypethunderbirdmonth'), 'thunderbirdmonth');
             $archive_type->add($this->gettext('archivetypesender'), 'sender');
             $archive_type->add($this->gettext('archivetypefolder'), 'folder');
 
diff --git a/plugins/archive/localization/en_CA.inc b/plugins/archive/localization/en_CA.inc
index 06b78fb2a..15dba5f03 100644
--- a/plugins/archive/localization/en_CA.inc
+++ b/plugins/archive/localization/en_CA.inc
@@ -25,6 +25,7 @@ $labels['settingstitle'] = 'Archive';
 $labels['archivetype'] = 'Divide archive by';
 $labels['archivetypeyear'] = 'Year (e.g. Archive/2012)';
 $labels['archivetypemonth'] = 'Month (e.g. Archive/2012/06)';
+$labels['archivetypethunderbirdmonth'] = 'Month - Thunderbird compatible (e.g. Archive/2012/2012-06)';
 $labels['archivetypefolder'] = 'Original folder';
 $labels['archivetypesender'] = 'Sender email';
 $labels['unkownsender'] = 'unknown';
diff --git a/plugins/archive/localization/en_GB.inc b/plugins/archive/localization/en_GB.inc
index a6a5f6d80..3661da4be 100644
--- a/plugins/archive/localization/en_GB.inc
+++ b/plugins/archive/localization/en_GB.inc
@@ -25,6 +25,7 @@ $labels['settingstitle'] = 'Archive';
 $labels['archivetype'] = 'Divide archive by';
 $labels['archivetypeyear'] = 'Year (e.g. Archive/2012)';
 $labels['archivetypemonth'] = 'Month (e.g. Archive/2012/06)';
+$labels['archivetypethunderbirdmonth'] = 'Month - Thunderbird compatible (e.g. Archive/2012/2012-06)';
 $labels['archivetypefolder'] = 'Original folder';
 $labels['archivetypesender'] = 'Sender email';
 $labels['unkownsender'] = 'unknown';
diff --git a/plugins/archive/localization/en_US.inc b/plugins/archive/localization/en_US.inc
index 51bdb7b13..eadcc4956 100644
--- a/plugins/archive/localization/en_US.inc
+++ b/plugins/archive/localization/en_US.inc
@@ -27,6 +27,7 @@ $labels['settingstitle'] = 'Archive';
 $labels['archivetype'] = 'Divide archive by';
 $labels['archivetypeyear'] = 'Year (e.g. Archive/2012)';
 $labels['archivetypemonth'] = 'Month (e.g. Archive/2012/06)';
+$labels['archivetypethunderbirdmonth'] = 'Month - Thunderbird compatible (e.g. Archive/2012/2012-06)';
 $labels['archivetypefolder'] = 'Original folder';
 $labels['archivetypesender'] = 'Sender email';
 $labels['unkownsender'] = 'unknown';