[exim] Spam not being spam checked

Hi,

I´ve noticed recently that Ive been recieving spam that has not
been spam checked. I had a look in the exim config and the logic
controlling what is and what is not checked is the following (I
believe):

spamcheck:
   verify = false
   condition = \
     ${if !or{ \
         {eq{$received_protocol}{esmtpa}} \
         {eq{$received_protocol}{spam-scanned}} \
     } {yes} {no}}
   driver = accept
   transport = spamcheck_pipe
   headers_remove =  
X-Spam-Checker-Version:X-Spam-Score:X-Spam-Report:X-Spam-Level:X-Spam-Status:X-Spam-Flag:

Actually it was originally checking for recieved_protocol asmtp in the
if statement but I could see mail sent with authentication is actually
listed as esmtpa in the headers so I changed it to esmtpa thinking
this was more appropriate.
Is the above config appropriate or should I change it? Any advise?

thanks, Andy.