[exim] Question about ACL's

Is it possible to do an RBL check after every RCPT TO in the ACLs?
And if so, could someone give me an example of how I could write this
ACL:
Message: Rejected by DNSBL check
Condition: if mysql SELECT local_part@domain FROM table WHERE dnsbl=1

I remember a while ago when I was looking at ACL's, local_part was not
available, but surely after each RCPT TO line it should be??

-- 
Avleen Vig
Systems Administrator
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