smp_affinity weirdness in LK 2.6.14

Hello,

I found that I cannot change IRQ affinity in the 2.6.14 kernel. It works
however on the 2.6.13.4 and earlier.
2.6.13.4:
# cat /proc/irq/189/smp_affinity
1
# echo 2 > /proc/irq/189/smp_affinity
# cat /proc/irq/189/smp_affinity
2
#

2.6.14:
# cat /proc/irq/189/smp_affinity
1
# echo 2 > /proc/irq/189/smp_affinity
# cat /proc/irq/189/smp_affinity
1
#
/proc/interrupts is also showing that all all IRQs are bound to CPU0. I
must add, that this system is a P4 with HyperThreading support. I've
tried both with CONFIG_IRQBALANCE=y and n but the result is always the
same. With the new kernel I cannot balance the IRQs neither by hand, nor
userspace/kernel tools. Is that normal?

Regards
-Dimitri