a simple solution is to 'zip' the attachment before you attach it.
I run a number of programs via the 'net' and it is a condition for all assignments that files are zipped before they are sent to me. If i do receive an unzipped file, i reply to the sender "unzipped assignment - assignment still outstanding - you file has been deleted, please resend in the required format"
Myrna Komar
The Trainer from Down Under