diff --git a/lib/models/fields.js b/lib/models/fields.js
index 404cdfe2..a35c1c16 100644
--- a/lib/models/fields.js
+++ b/lib/models/fields.js
@@ -348,7 +348,7 @@ function addCustomField(listId, name, defaultValue, type, group, groupTemplate,
                     case 'date-eur':
                     case 'birthday-us':
                     case 'birthday-eur':
-                        query = 'ALTER TABLE `subscription__' + listId + '` ADD COLUMN `' + column + '` TIMESTAMP NULL DEFAULT NULL';
+                        query = 'ALTER TABLE `subscription__' + listId + '` ADD COLUMN `' + column + '` DATETIME NULL DEFAULT NULL';
                         indexQuery = 'CREATE INDEX ' + column + '_index ON `subscription__' + listId + '` (`column`);';
                         break;
                     default: