Neoterisis Netscreen

I am trying to use a Cisco ACS Radius server to authenticate to a
Netscreen SSL VPN.  I set the ACS servers in the Netscreen configuration
and defined the object on the Cisco ACS box.  Two questions I have:

 

Do user accounts have to be setup on the Netscreen box or will Netscreen
pull these accounts in from ACS. 

Is there anything additional that needs to be configured and does it use
IETF Radius.