The "block fragmented IP Packets" option in Symantec Norton Personal Firewall 2002 (NPW) does not properly protect against certain attacks on Windows vulnerabilities such as jolt2 (CVE-2000-0305).
http://www.securityfocus.com/bid/4545
http://securityresponse.symantec.com/avcenter/security/Content/2002.05.16.html