[Exim] My filter still lets thro ..exes

Hello,

I have just copied Nigel Metheringham system filter, but for some reasons... emails with .exe and .com attachments
are still passing through.
am running exim 3.2 and my configs are as follows:

smtp_accept_max = 600
smtp_accept_max_per_host = 40
remote_max_parallel = 20
message_size_limit = 10485760
return_size_limit = 1024
sender_reject = "lsearch;/usr/local/exim/badmailfrom"
message_filter = /usr/local/exim/system_filter.test
timeout_frozen_after = 2d
ignore_errmsg_errors
auto_thaw=4h



i have named the filter file system_filter.test

please assist.

rgds
tdn