[Exim] Return error message without the attach?

Hi

I don't want a copy of the failed messages in the return error message,
at least , I want to drop de attach in the original messages.

I try to set the return_size_limit to 0 but this don't work.

The reason: I'm running exim with a system filter for executable file
attach and a a mail virus scanner, (amavis), when the filter hunt a
virus
then a errmsg is sent to sender with a copy of the virus in it. then
the virus mail software block the return error message and it never go
to the sender.

How Can I drop all attach in the return error message? (or don't send a
copy of the original message, I don't need it)

Thanks in adventage

Excuse my poor English.