diff --git a/db/update9.3.beta.sql b/db/update9.3.beta.sql
new file mode 100644
index 0000000000..1a241ea247
--- /dev/null
+++ b/db/update9.3.beta.sql
@@ -0,0 +1,4 @@
+alter table zt_bug modify column mailto text;
+alter table zt_story modify column mailto text;
+alter table zt_task modify column mailto text;
+alter table zt_testtask modify column mailto text;
diff --git a/db/zentao.sql b/db/zentao.sql
index bf500ff379..a0e4d3b78e 100644
--- a/db/zentao.sql
+++ b/db/zentao.sql
@@ -68,7 +68,7 @@ CREATE TABLE IF NOT EXISTS `zt_bug` (
   `color` char(7) NOT NULL,
   `confirmed` tinyint(1) NOT NULL default '0',
   `activatedCount` smallint(6) NOT NULL,
-  `mailto` varchar(255) NOT NULL default '',
+  `mailto` text,
   `openedBy` varchar(30) NOT NULL default '',
   `openedDate` datetime NOT NULL,
   `openedBuild` varchar(255) NOT NULL,
@@ -353,7 +353,7 @@ CREATE TABLE IF NOT EXISTS `zt_group` (
   `name` char(30) NOT NULL,
   `role` char(30) NOT NULL default '',
   `desc` char(255) NOT NULL default '',
-  `acl` text NOT NULL default '',
+  `acl` text,
   PRIMARY KEY  (`id`)
 ) ENGINE=MyISAM  DEFAULT CHARSET=utf8;
 -- DROP TABLE IF EXISTS `zt_grouppriv`;
@@ -513,7 +513,7 @@ CREATE TABLE IF NOT EXISTS `zt_story` (
   `product` mediumint(8) unsigned NOT NULL default '0',
   `branch` mediumint(8) unsigned NOT NULL default '0',
   `module` mediumint(8) unsigned NOT NULL default '0',
-  `plan` text NOT NULL default '',
+  `plan` text,
   `source` varchar(20) NOT NULL,
   `sourceNote` varchar(255) NOT NULL,
   `fromBug` mediumint(8) unsigned NOT NULL default '0',
@@ -525,7 +525,7 @@ CREATE TABLE IF NOT EXISTS `zt_story` (
   `status` enum('','changed','active','draft','closed') NOT NULL default '',
   `color` char(7) NOT NULL,
   `stage` enum('','wait','planned','projected','developing','developed','testing','tested','verified','released') NOT NULL DEFAULT 'wait',
-  `mailto` varchar(255) NOT NULL default '',
+  `mailto` text,
   `openedBy` varchar(30) NOT NULL default '',
   `openedDate` datetime NOT NULL,
   `assignedTo` varchar(30) NOT NULL default '',
@@ -587,7 +587,7 @@ CREATE TABLE IF NOT EXISTS `zt_task` (
   `deadline` date NOT NULL,
   `status` enum('wait','doing','done','pause','cancel','closed') NOT NULL default 'wait',
   `color` char(7) NOT NULL,
-  `mailto` varchar(255) NOT NULL default '',
+  `mailto` text,
   `desc` text NOT NULL,
   `openedBy` varchar(30) NOT NULL,
   `openedDate` datetime NOT NULL,
@@ -705,7 +705,7 @@ CREATE TABLE IF NOT EXISTS `zt_testtask` (
   `pri` tinyint(3) unsigned NOT NULL default '0',
   `begin` date NOT NULL,
   `end` date NOT NULL,
-  `mailto` varchar(255) NOT NULL default '',
+  `mailto` text,
   `desc` text NOT NULL,
   `report` text NOT NULL,
   `status` enum('blocked','doing','wait','done') NOT NULL DEFAULT 'wait',