TCP is the most popular transport layer protocol. When there is congestion in the network, either sender¡¦s TCP or router¡¦s buffer management has its way to resist the penalties of congestion. But each of them achieves this goal in an independent way. In TCP, Tahoe, Reno, New Reno, SACK, Vegas, FACK, and some modifications to TCP to improve performance were proposed. Although they have better performance than previous TCP, the cooperation between different types of TCP is not well. And TCP-unfriendly connections will be adverse to TCP connections. In buffer management, the fairness between different connections can be maintained. But some phenomena will be adverse to TCP connection because of buffer management is TCP-unawareness. In this paper, we show a problem that buffer management scheme may be unfriendly to new connection which is going to join the network with congestion. This problem will incur (1) TCP-unfriendly behavior, (2) alleviating congestion inefficiently, (3) unfairness between two connections. We propose a scheme to alleviate this problem and this scheme is easy to implement with existing buffer management scheme.