>Although until a few days ago everything worked fine, now I can't send
>mail with sendmail to the relay host 'mail.mclink.it'.  I get the following
>error:
>
>$ sendmail -v -q -d8.7
>
>Running MAA00454 (sequence 1 of 1)
>getmxrr(mail.mclink.it, droplocalhost=1)
>getmxrr: res_search(mail.mclink.it) failed (errno=60, h_errno=2)
>Federico_Lupi@mail.datasys.it... Deferred: Name server: mail.mclink.it:
>host name lookup failure

	I think you have some reachability problem to DNS server from
	sendmail.  not sure why you are okay with dnsquery.  make sure
	that you put reachable DNS server into /etc/resolv.conf.

itojun