PHP warning in facebook.php line 60

Hi,

I'm getting the following PHP warning many times per day. Sometimes more than once per second, sometimes only once per hour.
Perhaps you can have a look on it to fix it in the next version.

PHP Warning: session_start(): Cannot send session cache limiter - headers already sent in /.../wp-content/plugins/wpmu-dev-facebook/lib/external/facebook.php on line 60

Thanks,
Martin