Authentication time-out not work.

  Hi, all, on the Fortigate 310b (5.2.3,build670 (GA)) with two vdoms, i make this:

config vdom
edit vdom1
config user setting
set auth-timeout 30
set auth-timeout-type idle-timeout
end

fgt310b (setting) # show
config user setting
    set auth-timeout 30
end

But the time-out doesn't work with 30 minutes! (i thinks is the default: 5m)

In global configuration doesn't have this configuration:

fgt310b (global) # config user setting ?
device-category Configure device categories.

What i'm doing wrong?

Thanks!