It would me quite nice if it would be possible to send
mail without the need to specify a mail server, by
using MX records from DNS.
Logged In: NO
This has been discussed on the Blat mailing list before, and
the basic answer is no. This type of request is often
associated with spamming, and the use of MX records is
supposed to be a server function, not a client function.
Blat is designed to be a user (client) program to send
messages to their own server, not designed to be a server