File Upload Problem

Hi All I'll start by saying that I've checked the online manual (and comments) as well as having done a Google search on this with no success. My problem is that files uploaded through a form are increasing in size. For example, I upload an image that is 7658 bytes and the uploaded version is 7685 bytes, or upload 11106 bytes and it's 11133 bytes when uploaded. Images uploaded through my form are broken in the process and no longer display. This is only happening on my production server (RH Linux-based). My development environment is Win XP with Apache and PHP and the exact same code works perfectly. I've checked through /etc/php.ini for anything related without success. I use move_uploaded_file() to handle the uploaded file once it's on the server. Can anyone suggest where else I should be looking to resolve this? Thanks, Dave