Qpopper (version 4.0.4, at least) does not provide an easy way to disable support for the XNTD XMIT command. In order to disable it when I built qpopper for our site, I had to remove its entry from the subcommands table in popper/pop_get_subcommand.c.
IMO, any feature that cannot be disabled is a bug. Qpopper should provide an easy mechanism (a ./configure flag, a qpopper command-line flag, and/or a config file variable) to disable this feature. If the qpopper maintainers would be willing to accept it, I'd be willing to produce a patch to implement the above behavior. Let me know. -- James Ralston, Information Technology Software Engineering Institute Carnegie Mellon University, Pittsburgh, PA, USA
