ACP: searching for users does not show inactive accounts

When using "find a member" link in acp to find user, popup does not list accounts that aren't active.

This poses a problem for admin when trying to find someone by parameters other than user name. Example: a user is getting "email address is taken" error when registering, but that email is used by account he forgot about that isn't active. Without knowing account name, admin won't be able to help that user.