An ASA 5510 running ASA software version 7.2(3) as an IPSec LAN2LAN VPN gateway is spamming the log with bursts of messages:
Feb 18 06:40:12 x.x.x.x %ASA-5-713904: Group = y.y.y.y, IP = y.y.y.y, All IPSec SA proposals found unacceptable! Feb 18 06:40:12 x.x.x.x %ASA-3-713902: Group = y.y.y.y, IP = y.y.y.y, QM FSM error (P2 struct &0x472b280, mess id 0xd375a6ce)! Feb 18 06:40:12 x.x.x.x %ASA-3-713902: Group = y.y.y.y, IP = y.y.y.y, Removing peer from correlator table failed, no match!
Where x.x.x.x is the IP address of the ASA in question and y.y.y.y is the IP address of the IPSec peer, a PIX 515 running version 6.3(5). The hex values behind "QM FSM error" vary.
These three lines typically repeat every 5 seconds for 2-3 minutes and then stop. The CCO Error Message Decoder is particularly unhelpful on message 713902 and doesn't even know message 713904.