This problem seems directly related to the infamous 2GB limit and I\'m not sure at this atge if its a 32bit PHP issue. I\'ve seen the comments related to HTTP not being desi
The question is why would you use your browser to upload > 1GB. Consider top file sharing services most limit file upload size to 1GB via browser. What happens if user-download fails you would have to restart the whole process.
Have you looked in to alternatives if you have such large file uploads, torrents, ftp or personal upload client like rapidshare, fileupload, megaupload etc. Have.
You are limited because of the file size limit set to POST's. If you are determined to use HTTP to upload bigger files which i would discourage, the optimal solution would be spliting the file and uploading the smaller splited parts then reassembling the file.