This port based on proxing qmail-queue component of Qmail. You can
enable this port by two different ways:

1. Move qmail-queue to qmail-queue.original, then move
   qmail-queue.drweb to qmail-queue.
2. If Qmail built WITH_QMAILQUEUE_PATCH, You can set
   QMAILQUEUE variable to full path of qmail-queue.drweb,
   then specify old qmail-queue in drweb_qmail.conf instead
   of default qmail-queue.original. Read Qmail docs for details.