might cause your system to hang during boot up. Please, be advised, that instructions regarding automatic startup and shutdown Oracle 10gR2 on RHEL AS 4.X suggested by Tim@oracle-base.com are valid only for non-ASM databases
Just read carefully the comments to $ORACLE_HOME/bin/dbstart:-
# If ASM instances are to be started with this script, it cannot
# be used inside an rc*.d directory, and should be invoked from
# rc.local only. Otherwise, the CSS service may not be available
# yet, and this script will block init from completing the boot
View Jeff Hunter's article Installing Oracle10g Release 1 (10.1.0) on Linux - (RHEL 4)
at http://www.idevelopment.info regarding final step to manually edit the script /etc/inittab so that the entry to respawn init.cssd comes before running the runlevel 3.