[tor-onions] qmail as MTA to .onion emails

[grarpamp]

Yes a wrapper for setting "LD_PRELOAD sendmail" if
needed since some MUA's might not have a way to specify
an env like that when calling out.
Or LD_PRELOAD the MUA itself.

qmail-send is the sending side MTA parent daemon,
not any sendmail-like (that MUA function is above).

Qmail can use piped progs in startup shell, lots of
file descriptors and env vars.
LD_PRELOAD thus needs applied in that context
to each where applicable.

It should work once figured out.

Some people in onion / i2p have documented
various MTA setups there.

Transproxy is big hammer kernel packet filter.
LD_PRELOAD is fine tooth userland libs.
Bad or good and which, is up to the user to determine.