The packet size `40` is incompatible with the TCP Option MSS who takes 4 octets.

diff --git a/etc/pf.os b/etc/pf.os
index 41c1bc6a482..4890b3785d0 100644
--- a/etc/pf.os
+++ b/etc/pf.os
@@ -617,7 +617,7 @@ S1:255:1:60:M1460,S,T,N,W0: LookSmart:ZyBorg::LookSmart ZyBorg

65535:255:0:48:M*,N,N,S: Redline:::Redline T|X 2200

-32696:128:0:40:M1460: Spirent:Avalanche::Spirent Web Avalanche HTTP benchmarking engine
+32696:128:0:44:M1460: Spirent:Avalanche::Spirent Web Avalanche HTTP benchmarking engine

# ----------- Embedded systems --------------