$_FILES['myfile']['error'] is zero, but there's no file uploaded

I'm trying to copy a production server onto an old Mac running 10.5. Everything works great, except uploading files.

Unfortunately, there are no errors being reported either by PHP or apache, just no file at the end. I've been setting permissions of everything I can find to 777, but no luck - even the simplest uploader tutorial produces a $_FILE['myfile']['error'] of zero, but when I look for the file listed in $_FILE['myfile']['tmp_name'] the file does not exist.

Any suggestions?

I've tried the built-in OSX versions of apache and PHP 5.2开发者_如何学Go, and I've tried installing apache2 and PHP 5.3.4 from MacPorts. Both have the same results.

I figure this must be a permissions problem some place, but why don't I get an error?

Please check the HTML of File Uploader. Its FORM tag must contain

ENCTYPE = "multipart/form-data" 

To upload any file.