make check fails on OS X 10.6.2

All,

I've been installing postgres from source on os x for years, but I haven't generally run 'make check' before I install.
Idon't feel that running 'make check' is terribly necessary in this case - it's a personal sandbox on my laptop, with
noproduction value. Regardless, I realize that it's beneficial, so I took the extra time today, and ran across this
problem.

I've got 8_4_STABLE checked out from CVS, and I've run configure as follows:

./configure --with-bonjour --with-python --with-perl

Configure completed, and 'make' ran successfully.

The relevant output from 'make check' is:

./pg_regress --inputdir=. --dlpath=. --multibyte=SQL_ASCII --load-language=plpgsql  --temp-install=./tmp_check
--top-builddir=../../..--schedule=./parallel_schedule   
============== creating temporary installation        ==============
============== initializing database system           ==============

pg_regress: initdb failed
Examine /Users/thart/projects/pgsql/src/test/regress/log/initdb.log for the reason.
Command was: "/Users/thart/projects/pgsql/src/test/regress/./tmp_check/install//usr/local/pgsql/bin/initdb" -D
"/Users/thart/projects/pgsql/src/test/regress/./tmp_check/data"-L
"/Users/thart/projects/pgsql/src/test/regress/./tmp_check/install//usr/local/pgsql/share"--noclean >
"/Users/thart/projects/pgsql/src/test/regress/log/initdb.log"2>&1 

And the contents of src/test/regress/log/initdb.log is:

creating directory /Users/thart/projects/pgsql/src/test/regress/./tmp_check/data ... ok
creating subdirectories ... ok
selecting default max_connections ... 10
selecting default shared_buffers ... 400kB
creating configuration files ... ok
creating template1 database in /Users/thart/projects/pgsql/src/test/regress/./tmp_check/data/base/1 ... FATAL:  could
notcreate shared memory segment: Cannot allocate memory 
DETAIL:  Failed system call was shmget(key=1, size=1613824, 03600).
HINT:  This error usually means that PostgreSQL's request for a shared memory segment exceeded available memory or swap


initdb can and does create a valid database cluster when run by itself, and so far I haven't had any issues with 8.4
duringvery casual use. 

Tim