MIME ACL problem

Folks,

someone reported this problem about a month back but the thread wasn't
replied to on list. We have recently upgraded to the latest version of
exiscan and I have changed the exim configure file to take account of the
new mime acl. However, it produces large numbers of the following error -

"temporarily rejected during MIME ACL checks: cannot test demime condition
in MIME ACL"

The relevant sections of our configure file are thus -

# Set ACL to be run on MIME parts
acl_smtp_mime = acl_check_mime

	....

acl_check_mime:
  # Reject potentially executable attachments
  deny    message       = Message contains potentially executable attachment
          demime        = ade:adp:bas:bat:chm:cmd:com:cpl:exe:hlp:hta:\
 
inf:ins:isp:js:jse:lnk:mdb:mde:msc:msi:msp:mst:pcd:pif:\
                          reg:scr:sct:shs:shb:url:vb:vbe:vbs:wsc:wsf:wsh

  deny    message       = Malware $malware_name detected
          malware       = *

  accept

acl_check_data:

	[spamassassin etc.]

Have I missed something obvious here?

Thanks,

 Clive McDowell

Information Services
The Queen's University of Belfast