Vulnerability found ... by nessus

Vulnerability found on port general/tcp The remote host seems to generate Initial Sequence Numbers (ISN) in a weak manner which seems to solely depend on the source and dest port of the TCP packets. The Raptor Firewall is known to be vulnerable to this flaw, as may others be. An attacker may use this flaw to establish spoofed connections to the remote host. This what I get if I probe a host runing SuSE Pro 8.1 ... Is there a patch or something ?