PowerPC question

[Smith, Gene]

This is not really directly related to rtems but since there seems to be 
a lot of powerpc users here I thought I would ask.

My timer interrupt is implemented using the PIT at vector offset 0x1000. 
  Should setting the MSR register to 0x21000 (EE bit off) disable the 
timer interrupt? This is for ppc405gpr. For some reason I still seem to 
see the timer interrupt when MSR is set to this or even when set to 0.

Thanks,
-gene