Revision history for Queue-DBI

1.6     12/16/2011
        Added more documentation and tests. Public release.

1.5     08/19/2010
        Prevented locking twice a queue element.

1.4     08/05/2010
        Fixed problem with the internal max_id cache preventing runaway
        dequeueing (dequeue-enqueue-dequeue would fail on the last dequeue to
        see the last enqueued element when using the same $queue object).

1.3     08/03/2010
        Added option to limit how many times a queue element can be requeued
        before it stops being pulled.

1.2     06/28/2010
        Modified requeue() - returns error without a die() to indicate a problem
        that is not the responsibility of this module.
        Improved algorithm to detect possible parallelization conflicts.

1.1     06/18/2010
        Locking mechanism improvements, courtesy of Jamie McCarthy.

1.0     11/21/2009
        First version.