Make a file in /etc called rc.oracle - the contents are
#!/bin/ksh
su - oracle -c /u05/app/oracle/product/8.0.5/bin/dbstart # Start all local Databases
su - oracle -c /u05/app/oracle/product/8.0.5/bin/lsnrctl start # Start the Oracle Listener
su - oracle -c /u05/app/oracle/product/8.0.5/bin/lsnrctl dbsnmp_start # Start the Intelligent Agent
Make another file in etc called rc.shutdown - the contents are
su - oracle -c /u05/app/oracle/product/8.0.5/bin/lsnrctl stop
su - oracle -c /u05/app/oracle/product/8.0.5/bin/dbshut
In your /etc/inittab put this entry
oracle:2

nce:/etc/rc.oracle >/dev/console 2>&1
The rc.shutdown will be found when the system shuts down
The rc.oracle will be run from inittab when the system starts
I don't have access to HACMP, so can't help if you have that, but this all works for AIX 4.3.3
Alex