We have Google apps in our company for mail delivery, our business can't pay the business version yet, however, we need to control the attachment types that employees download.

We recently switched from another hosting provider who recomended us to plug Google Apps for mail when we moved the domain, we had a firewall before which was able to prevent certain file types to be downloaded.

I know the business version has section for filtering mail (postini services). Is there a hack around my problem? Anyone ever had this problem? Thank you!

UPDATE:

The main problem is gmail apps uses ssl connection, can this be changed ? how can i get the firewall to filter files only allowing *.doc, *.xls y *.pdf.