What is "doing a peer verify"?

["Rosenbaum, Larry M." <rosenbaumlm@xxxxxxxx>]

What does the following syslog message mean (and why is it an "error")?

Sep  8 10:20:39 email imap[17952]: [ID 160154 local6.error] Doing a peer
verify

name       : Cyrus IMAPD
version    : v2.3.3 2006/02/28 13:00:45
vendor     : Project Cyrus
support-url: http://asg.web.cmu.edu/cyrus
os         : SunOS
os-version : 5.9
environment: Built w/Cyrus SASL 2.1.21
             Running w/Cyrus SASL 2.1.22
             Built w/Sleepycat Software: Berkeley DB 4.4.20: (January
10, 2006)
             Running w/Sleepycat Software: Berkeley DB 4.4.20: (January
10, 2006)
             Built w/OpenSSL 0.9.8a 11 Oct 2005
             Running w/OpenSSL 0.9.8a 11 Oct 2005
             CMU Sieve 2.3
             TCP Wrappers
             mmap = shared
             lock = fcntl
             nonblock = fcntl
             idle = idled
----
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