TCP problems after 124 days of uptime?

Yesterday two of our web servers running 6.2-PRERELEASE experienced
problems with accepting TCP connections. A small percentage of SYN
packets was ignored. The packets were seen in tcpdump output, but not
processed by TCP stack. No accept queue overflows occured, according
to 'netstat -sp tcp'.

Failing to find any clue I have rebooted one of them, and after
reboot is started to work flawlessly. Reboot also helped the second
one. Both servers were booted at the same time - 124 days ago.

Any ideas, any similar reports?

Totus tuus, Glebius.
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