Problem starting PG-9.2 on non-default port

I wish to run an instance of PG-9.2 concurrently with our production
version (9.1). I have changed the listening port number.

listen_addresses = 'pgsql-dbms.hamilton.harte-lyne.ca, localhost'
#port = 5432 # (change requires restart)
port = 5433

However, I am getting this error when I try to start the new version
while the old one is still running. Is there something else I must do
to accomplish this? Why is the lock file using the default port
number for this instance?

cat ../pgstartup.log
2012-12-14 09:13:41 EST : LOG: XX000: could not bind IPv4 socket:
Address already in use
2012-12-14 09:13:41 EST : HINT: Is another postmaster already
running on port 5432? If not, wait a few seconds and retry.
2012-12-14 09:13:41 EST : LOCATION: StreamServerPort, pqcomm.c:438
2012-12-14 09:13:41 EST : WARNING: 01000: could not create listen
socket for "pgsql-dbms.hamilton.harte-lyne.ca"
2012-12-14 09:13:41 EST : LOCATION: PostmasterMain, postmaster.c:892
2012-12-14 09:13:41 EST : FATAL: F0001: lock file
"/tmp/.s.PGSQL.5432.lock" already exists
2012-12-14 09:13:41 EST : HINT: Is another postmaster (PID 1299)
using socket file "/tmp/.s.PGSQL.5432"?
2012-12-14 09:13:41 EST : LOCATION: CreateLockFile, miscinit.c:822

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James B. Byrne mailto:ByrneJB(at)Harte-Lyne(dot)ca
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