@command{nncp-xfer} checks if locally copied packet's checksum differs
from the source's one.
+@item
+@command{nncp-ack} command appeared, that sends explicit packet receipt
+acknowledgement (ACK packet). That acknowledgement deletes referenced
+packet from the outbound spool.
+
@item
Ability to turn @code{fsync} operation off using @env{$NNCPNOSYNC=1}
environment variable.