PROBLEM: Wrong Setup of SMP irq affinity on X86_64 2.6.1

2.

It seems that the smp-affinity value gets initialized the wrong way on boot. On my 2 cpu opteron 240 Machine all interrupts get delivered to cpu0. When I cat the current setting of the /proc/irq/#/smp_affinity it shows a value of '3' . When setting it manually to ffffffffffffffff
interrupts get delivered to both cpus as it should be.

Could this be an endianess issue, as 3 would be ok, if the first two cpus should be enabled, but not if bytes get swapped?

3.
kernel, smp, irq_affinity, x86_64

4.
Linux version 2.6.1-gentoo (root@orthrus) (gcc-Version 3.3.2 20031022 (Gentoo Linux 3.3.2-r2, propolice)) #6 SMP Tue Jan 13 13:13:30 CET 2004

5.,6.
-not applicable-

7.1
Linux orthrus 2.6.1-gentoo #6 SMP Tue Jan 13 13:13:30 CET 2004 x86_64 5
GNU/Linux

Gnu C                  3.3.2
Gnu make               3.80
util-linux             2.11z
mount                  2.11z
module-init-tools      3.0-pre5
e2fsprogs              1.33
reiserfsprogs          3.6.8
nfs-utils              1.0.5
Linux C Library        2.3.2
Dynamic linker (ldd)   2.3.2
Procps                 3.1.13
Net-tools              1.60
Kbd                    1.06
Sh-utils               5.0.91
Modules Loaded         sd_mod sg floppy nvidia bcm5700

7.2
processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 5
model name : AMD Opteron(tm) Processor 240
stepping : 1
cpu MHz : 1403.211
cache size : 1024 KB
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 syscall nx mmxext lm 3dnowext 3dnow
bogomips : 2744.32
TLB size : 1088 4K pages
clflush size : 64
address sizes : 40 bits physical, 48 bits virtual
power management: ts ttp

processor : 1
.. same as above..

rest...
not applicable or unnescesarry

Greets

Martin Polak