hmmm - could be a few things.
Firstly - it looks like you have a typo in your code. You call the input type "fupload" then refer to it as "fuploada". I assume that this is just when you pasted it into here though.
Once this has been fixed how about trying the following...
where does the upload fail? Does it actually upload a file, but not match your type's specified in your if statement. Rememebr Mac's don't rely on extensions etc, just associations within the file which have casued me some problems before. Make sure photoshop save the files WITH an extension otherwise the JPEG file becomes a non-standard JPEG format, and browsers don't like it (especially IE). Anyhow - try taking out the "if" statement and seeing what happens then. See what type is being set for the file being uploaded.
If it is not even uploading the file, then what browser etc are you using?
Hope this helps you in some way.