qpsmtpd queue plugin?

Greetings,

I've been investigating using this module with qpsmtpd.  Does such a 
plugin already exist?

I hacked together a quick proof of concept to test performance of the 
methods and found roughly:

$dq->enqueue_file:     2600 msg/min
$dq->enqueue_string: 2900 msg/min

Note these are qpsmtpd #s and the queue dir lives on a NFS mounted 
volume so it isn't showing IPC::DirQueue performance.

It also seems that when using the enqueue_file method the original file 
still exists and has to be rm'd separately?  Is this expected?  My 
assumption (love em) was that the original file would be re-linked into 
the queue.

Cheers,

ds