"In a battery of more than three thousand different tests, Blue Lane's solution was able to demonstrate its knowledge of various Microsoft protocols and prove its ability to accurately process them and ensure the network server traffic was acceptable with no false positives."
Greg Ness, VP bluelane, when asked, mentioned:
To my knowledge this is the first time that any software vendor has tested and found no adverse traffic impacts - no false positives - in a third party network security appliance deployed to protect servers from malicious attacks. This is a particularly important development for the protection of servers because the false blocking of traffic has a considerable impact on server availability. False positives in established network security appliances have forced many to deploy server protection in alarm-only mode, since the consequences of blocking good traffic can outweigh the risks of an attack and take down critical infrastructure. Alarm-only however is the equivalent of crying wolf if it isn't accurate. It still offers no real protection without additional intervention.
Check out MS's announcement.