Don't temp-fail on random address check.

If the address has successfully been checked,
but the subsequent check of a random address
is failing with a 4xx response (or a network
problem pp.), the address has been validated
and should be handled that way.

Signed-off-by: Thomas Hochstein <thh@inter.net>

checkmail.pl

@@ -224,6 +224,9 @@ sub checksmtp {
         # connection failure?
         if ($success < 0) {
           $status = connection_failed(@message);
+          # reset status - the address has been checked and _is_ valid!
+          $status = 3;
+          print "  > Address verification currently impossible. You'll have to try again or send a test mail ...\n" if !($options{'q'});
         # verification impossible?
         } elsif ($success) {
           $status = 3;