[Dovecot] resilience suggestion

[Jakob Hirsch]

Quoting David Lee:

> We have had a source code hack since October (in "deliver.c", simply
> replacing a "return ret" occurence with "return EX_TEMPFAIL") and it has

I cannot speak for Timo, but if this means mail for non-existing users
will stay in the MTA's queue until it times out, it's definitely wrong.

Apart from that, nscd is one of the first things I remove from freshly
installed systems, because it's plain crap and caused only problems in
the past. Even though I can hardly believe they do not get even such
things right.