It runs in the qmail startup script to support all your existing .forward
 files automatically. Individual users can switch to the .qmail mechanism
 at their leisure.
 .
 dot-forward supports forwarding, program deliveries, and comments. It
 does not support file deliveries or :include: (However, it recognizes
 file delivery attempts, and defers delivery to give you a chance to set up
 a .qmail file).