postmaster.pid disappeared

Hi,
I was redirected to this maillist when i asked questions on irc. I
hope this is the right mailing list.
I am running postgresql 7.4.8 on solaris 10 (and I compile and
installed slony). Everytime I am trying to reload the configuration
using pg_ctl reload -D $PGDATA, it deleted the postmaster.pid and
didn't create a new one. So, after reload, the only way I can restart
the server is by kill -9 and then start the server again. I check the
log, nothing is meaningful except the last line:
LOG: received SIGHUP, reloading configuration files
I am wondering if anybody has any idea?

I also noticed that the pg_ctl stop $PGDATA -m fast and smart takes
forever. When I do ps -ef, i saw several instances of <defunct>. I
have to kill -9 almost all the time to shutdown the server.

Thank you in advance,

J