Failed running extprograms execute via socket - fatal recv(MSG_PEEK) failed disconnected

[E.B.]

> > Last two changes should fix this:
>
>
> Not yet -- this may be unrelated(?) but here is what I have
> after installing the newest source package:
> 
> Error: Couldn't load required plugin /usr/local/lib/dovecot/lib90_sieve_plugin.so:
> dlopen() failed: /usr/local/lib/dovecot/lib90_sieve_plugin.so: undefined symbol:
> mail_deliver_ctx_get_log_var_expand_table

Oh i guessing this requires the newest Dovecot source too (maybe you
should put notice on the wiki that extprograms run-via-socket is broken until
a new release?)

After installed newest Dovecot and Sieve, I getting this:

dovecot: lmtp(test at example.com): Debug: auth input:
dovecot: lmtp(testl at example.com): Fatal: master: service(lmtp): child 7033 killed with signal 11 (core dumps disabled)

With set mail_debug=yes doesn't give anything else of interesting for this.