Sometimes it happens that the expired signal is received while the
there's a new request in flight.
This happens in cases such as:
1) We send a request (A)
2) We get disconnected from the mailserver
3) We connect to a new mailserver
4) We send a request (B)
5) We receive an expired signal for A
In such cases the request should not be retried or counted as a failure.
Signed-off-by: Igor Mandrigin <i@mandrigin.ru>
Andrea Maria Piana
edf810444d