New CI 1.7 session class database error

[eluser]Unknown[/eluser]
Hi guys,when I using SQL Server as my database, I meet this bug again just as you had descript. Here is my solution:

=======================================================
--- system\libraries\Session.php 2008-10-18 13:36:48.000000000 +0800
+++ application\libraries\Session.php 2008-11-16 12:15:39.046875000 +0800
@@ -14,6 +14,7 @@
*/

// ------------------------------------------------------------------------
+define('USER_AGENT_MAX_LENGTH', 196);

/**
* Session Class
@@ -182,7 +183,7 @@
}

// Does the User Agent Match?
- if ($this->sess_match_useragent == TRUE AND trim($session['user_agent']) != trim(substr($this->CI->input->user_agent(), 0, 50)))
+ if ($this->sess_match_useragent == TRUE AND trim($session['user_agent']) != trim(substr($this->CI->input->user_agent(), 0, USER_AGENT_MAX_LENGTH)))
{
$this->sess_destroy();
return FALSE;
@@ -309,11 +310,11 @@
$this->userdata = array(
'session_id' => md5(uniqid($sessid, TRUE)),
'ip_address' => $this->CI->input->ip_address(),
- 'user_agent' => substr($this->CI->input->user_agent(), 0, 50),
- 'last_activity' => $this->now
+ 'user_agent' => substr($this->CI->input->user_agent(), 0, USER_AGENT_MAX_LENGTH),
+ 'last_activity' => $this->now,
+ 'user_data' => ''
);

-
// Save the data to the DB if needed
if ($this->sess_use_database === TRUE)
{
=======================================================

As you can see, I had make two changes:
1),change the length of 'USER_AGENT',50 is really bother me sometimes;(Of course you have to change your table's definition to adapt your setting first)
2),Add default 'user_data' value when insert new session record.

It is work fine for me,if you have any issue,please contact me.