MDB2 Error

[ext4]

Using latest revision of roundcube, 3994.  Php-fpm 5.3, nginx 0.7.65.


2010/09/28 02:56:22 [error] 1765#0: *54 FastCGI sent in stderr: "MDB2 Error: unknown error (-1): _execute: [Error message: Unable to execute statement]
[Last executed query: INSERT INTO session
       (sess_id, vars, ip, created, changed)
       VALUES (?, ?, ?, FROM_UNIXTIME(1285642582), FROM_UNIXTIME(1285642582))]
[Native code: 0]" while reading response header from upstream, client: 127.0.0.1, server: , request: "GET /mail/?_task=mail HTTP/1.1", upstream: "fastcgi://127.0.0.1:9000", host: "", referrer: "https:///mail/?_task=mail"

Sorry I think I posted this in the wrong location.

I should add that if I switch the database to mysql instead of mysqli, it works fine.