pgAdmin 1.12.0 (Mac OS X 10.5) Start Service instability

I would like to report a strange instability issue when starting PostgreSQL 9.0
via pgAdmin in Mac OS X 10.5. My Service command is defined as:

sudo -u postgres /Library/PostgreSQL/9.0/bin/pg_ctl -D
/Library/PostgreSQL/9.0/data

Let's say the server is running and I enter pgAdmin. Running? correctly shows
Yes. If I right-click on the server and then Stop Service, the server stops
correctly and Running? correctly shows No. If I then right-click and try to
Start Service, pgAdmin hangs indefinitely. Via Terminal, executing "sudo -u
postgres /Library/PostgreSQL/9.0/bin/pg_ctl -D /Library/PostgreSQL/9.0/data
status" shows that the server is running, so pgAdmin did start it correctly,
even though it's still hanging. Now, when I execute "sudo -u postgres
/Library/PostgreSQL/9.0/bin/pg_ctl -D /Library/PostgreSQL/9.0/data stop" and go
back to pgAdmin, it actually stops hanging and resumes working normally! This
is always repeatable.

In summary, Start Service starts the server correctly, but never gives control
back to pgAdmin, which hangs until the server is stopped.

Please let me know if I can help you track down the root cause.

Regards,
Anton