Roundcube error no. [500]

[NDIS.NL]

Hello, when i try to login on roundcube it gives:

SERVICE CURRENTLY NOT AVAILABLE!
Error No. [500]

Then i checked the log and it gives:

[31-Oct-2010 13:41:21 +0000]: DB Error: _doQuery: [Error message: Could not execute statement]
[Last executed query: PREPARE mdb2_statement_mysql_4ac90cc13cbecb54bc66db87a861ef828bc7935c2 FROM 'UPDATE session SET vars = ?, changed = FROM_UNIXTIME(1288$
[Native code: 2006]
[Native message: MySQL server has gone away]
 in /var/www/html/roundcubemail-0.4/program/include/rcube_mdb2.php on line 262 (POST /roundcube/?_task=&_action=login)
[31-Oct-2010 13:41:21] PHP Fatal error:  Using $this when not in object context in Unknown on line 0

I realy dont know where to start to get this problem solved.
Could someone help me with this?

Thank you.

 

[tomtom901]

[Native message: MySQL server has gone away]

Would be a good start?

P.S. NL? Contact me through PB, I'll have a look at your system if you'd like.