[Mimedefang] exiting the filter before any processing

[Rolf]

hello

I've tried so many combinations and none work.  Feeling a bit silly.

Where can I put in mimedefang-filter a statement so that the filter 
exits before any processing happens based on $RelayAddr ??

I've tried a simple: return if ($RelayAddr eq "ip address");  in 
various parts of the filter but none make any difference. Do I need 
such a statement in each of the subroutines?

What am I missing and/or misunderstanding?

thanks

r.