shutdown and reboot do not work correct

Hi,
    I update everything this afternoon(both kernel and world). when i 
try to reboot or shutdown system,i find something goes wrong.After 
system output "All buffers synced" and "Accounting disabled",system does 
not power off as normal. the keyboard still works and when i press the 
power button ,it output "acpi: suspend request ignored (not ready yet)", 
"acpi: request to enter state S5 failed (error 6)". Any one meet same 
problem?



Thanks,
kevin