crash help, pgsql 7.2.1 on RH7.3

running pgsql 7.2.1 on redhat7.3 SMP. installed a hacked glibc to fix the
mktime() timezone problem for dates < 1970
(http://rpms.arvin.dk/glibc/rh73/i686/)

three times now the backend process has unexpectedly quit. what happens is
the postmaster process and the stats processes disappear and only the client
connection processes remain.

i don't see a core file. nothing interesting is mentioned in the logs except
for the usual redo post-mortem on startup, "database system was interrupted
at ...". i'm new to postgres admin, so i'm hoping folks can give some
direction as to where to begin solving this problem. it's happened about 3
times in two months.

now that 7.2.3 is out and fixes the mktime() problem i should probably
upgrade to that and revert to stock redhat glibc stuff. my concern is that i
have no idea what caused these events and i don't know what to do to ensure
that when it happens again i'll be able to determine the cause. what type of
logging and monitoring is recommended to report the health of a running
postgres?