Okay....
maybe the IE5 on mac does NOT send the actual filename.
Try this:
if(copy($SOUNDCLIP,"../cat/soundclip/tempfile")){
echo "<br>File Copy Sucessful";
}
I replaced the $file with a static name: tempfile.
If the above works, that means the problem is getting the filename from IE5/mac.
NOTE: i've only used a mac 3 years ago (and those were the powerpc ones... not good 'ol imacs :-).
-sridhar