I am curious if there is some other limitation here. I was able to upload anything under 2gb.. over that and I got that error.

My php.ini has these parameters set:

upload_tmp_dir = /var/uploadtemp/
upload_max_filesize = 10000M
post_max_size = 10000M
memory_limit = 256M

My ajax_multiplefiles.php:

$uploader->MaxSizeKB=10240000;