On Jun 1, 2006, at 1:16 PM, Ulf Erikson wrote:

With or without compression a PDF file is always a binary file. A common 

trick to force (mail) systems realize this is to add a few non-ASCII 

characters in a comment at the beginning of the file. Never heard of 

viewers needing this.. But if it helps someone and harms no one I guess 

it is safe to add such a comment

Here's a simple patch (pick your favourite binary characters):