HI Piotr,
as far as I can see that isn't possible - the option "other" to use a specific user/pw is only available in the AP settings for a single AP.
That would mean you'd need to use the GUI and set it one by one.
In that case I'd think the CLI is a little bit faster even you also need to do it one by one.
The commands.....
> ap
# to get a list of all the AP serial# you'd do a show
> show
>
> 802_1x
> peap
e.g.
V2110-1:ap:1231035490430000:802_1x# peap username1 password1
-Ron