diff --git a/include/class.queue.php b/include/class.queue.php
index 1741d4f96d0c94c13126d4ada8ca42b55a3b75ac..dddff9576fd7a00a48baf016b88e46c9c8696c0c 100644
--- a/include/class.queue.php
+++ b/include/class.queue.php
@@ -2196,7 +2196,7 @@ extends VerySimpleModel {
             return '';
 
         $val = $f->to_php($f->from_query($row, $this->primary));
-        if (is_numeric($val))
+        if (!is_string($val))
             $val = $f->display($val);
 
         return $val;