The code handles also mail from a mobile device as the signature is attached on the server.
Keep in mind that the tool is not meant to be used in an enterprise. The extension manager is able to handle a huge ammount of mails. It uses the same technique as "professional" solutions. The LS code needs some time to run. But the only effect should be a delay in delivery, as the extension manager waits for the LS Agent to finish and then releases the mail.
So you might see some mails queuing up in mail.box.