Mac IE 5.0 upload problem

Would any Mac expert help me out with this one. I have created an upload script with works fine for PC file and Mac files with IE 4.5, but it just would not work with IE5.0 Whenever I upload file with IE 5.0, after it gets to the server, the size becomes smaller by few hundred bytes, this ruin the file. If I download the file to a mac again, it becomes a white icon and cannot be opened. The $file_type tells me that it is "application/octet-stream". But on the other hand, doing the same thing on IE 4.5 will make the filesize larger by a few hundred bytes when it arrive at the server (I think the resource fork is included) and the upload file type is "application/x-macbinary". Anyone know how come IE5.0 seems to lost those bytes? Is it losing the resource fork? Do I have any control over what the browser will upload? BTW, I was testing with some Quark Express file. Any help is appreciated. Jason Lam