Correction - it's RHEL4 update 8
I could almost swear that I had seen it work last week .. I dont know what happened but now, it remains in timer mode.
On my RHEL4 U6 box, I've set the kernel to use the local apic (lapic option). yet, when I say, opcontrol -l, it says - in timer interrupt mode.
I've rebooted the machine after adding the lapic option.
Uname -a on my box shows this -
Linux gdnh1000.adx.ac4.yahoo.com 2.6.9-89.ELlargesmp #1 SMP Mon Apr 20 10:43:12 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux
The CPU is - Intel(R) Xeon(R) CPU E5530 @ 2.40GHz