freebsd stable - Apr 2008 - Lots of FIN_WAIT_1 TCP Connections and deadlock in zoneli state

Hi All,

I am running squid as reverse proxy on FreeBSD 7.0-R amd64.
After running for a while (~ 8 hours), the throughput degrades to very
very low rate.
I found the squid is in "zoneli" state and is already a bug report on
http://www.freebsd.org/cgi/query-pr.cgi?pr=106317

But after more investigation, I found there are lots of TCP
Connections in FIN_WAIT_1 and never close.

# netstat -an | grep FIN_WAIT_1 | wc -l
     823
# netstat -an | grep FIN_WAIT_1 | head
tcp4       0    273  192.168.1.1.80        61.62.121.195.64739    FIN_WAIT_1
tcp4       0  13448  192.168.1.1.80        163.22.44.102.58775    FIN_WAIT_1
tcp4       0  33304  192.168.1.1.80        163.32.61.253.2273     FIN_WAIT_1
tcp4       0  48416  192.168.1.1.80        24.78.35.230.61059     FIN_WAIT_1
tcp4       0  33580  192.168.1.1.80        140.130.102.8.24673    FIN_WAIT_1
tcp4       0  32009  192.168.1.1.80        163.23.57.133.38863    FIN_WAIT_1
tcp4       0  78112  192.168.1.1.80        122.146.0.210.21639    FIN_WAIT_1
tcp4       0  32046  192.168.1.1.80        140.130.102.8.23723    FIN_WAIT_1
tcp4       0  32120  192.168.1.1.80        140.128.194.130.56875  FIN_WAIT_1
tcp4       0  33580  192.168.1.1.80        163.21.235.230.33900   FIN_WAIT_1

Is there a timeout timer for the FIN_WAIT_1 state? Thank you for any
suggestions!