smp_affinity on RHAS 4.x

I am being told that smp_affinity for NICs isn't recommended on RHAS

I'm currently running Linux 2.6.9-11.ELsmp #1 SMP Fri May 20 18:25:30
EDT 2005 x86_64 x86_64 x86_64 GNU/Linux on an HP 585 4 dual-cores (AMD
Opteron (tm) Processor 850)

Is it true? Also, if so, how does one unset it since it seems to be
set to bind after reboot.