[Exim] exim 4 changes from exim 3

Hello

I'm trying to set up amavis on exim 4

I'm looking at instructions for setting up amavis on exim,
and it mentions adding the below at the begining of the
DIRECTORS CONFIGURATION,

amavis_director:
condition = "${if eq {$received_protocol}{scanned-ok} {0}{1}}"
driver = smartuser
transport = amavis

As far as I'm aware that configuration was in exim 3 and doesn't
appear in exim 4.

Can you tell me what has replaced the directors configuration if
anything, and if this is a suitable replacement in the exim.conf

#added for amavis 15/7/02

amavis_router:
      condition = "${if eq {$received_protocol}{scanned-ok} {0}{1}}"
      driver = smartuser
      transport = amavis

Please be verbose in responses, I'm new to this
thank you

--
Grainne Sheerin