recovery via base + WAL replay failure

I'm trying to demonstrate recovery using the "continuous archiving"
backup technique. I'm using 8.3 on Windows.

I made a base backup while the postgres was running using the following
batch file:

--------------------------
psql -d test_database -U user_name -c "SELECT pg_start_backup('test');"

7za a -tzip "C:\backup\base.zip" "C:\Program Files\PostgreSQL\8.3\data"

psql -d test_database -U user_name -c "SELECT pg_stop_backup();"
--------------------------

No indication of any errors. However, I am unable to recover. Here are
my steps:

1. Stop service, replace the data directory w/ the base backup.
2. Create recovery.conf with this setting:
restore_command = 'copy C:\backup\%f "%p"'
3. Try to start service

After about 90 seconds, the dos prompt displays:
"(postgres 8.3) service could not be started"
"The service did not report an error"

Does anyone know what I am probably doing wrong?

Thanks,
--Rob Adams