diff --git a/include/class.forms.php b/include/class.forms.php
index 2c3ec0da755cbfac1bd14b502c09c3ffa224a31f..0b54f965ed71154c1606305cc00ef0537ca2be69 100644
--- a/include/class.forms.php
+++ b/include/class.forms.php
@@ -1478,6 +1478,11 @@ class TextboxField extends FormField {
     function parse($value) {
         return Format::striptags($value);
     }
+
+    function display($value) {
+        $value = $value ?: $this->value;
+        return ($value == 0) ? '&#48' : Format::htmlchars($this->toString($value));
+    }
 }
 
 class PasswordField extends TextboxField {