Linux PHP Admin Upload Timeout

We have a website using a post script to upload both an audio and video file. After upload the video file is converted to .flv and the audio file is converted to MP3. We have gotten the conversion working recently and all seems well also the PHP upload script checks out good. For users with a faster internet connection the uploads go well and we receive a success message indicating that the upload has succeeded. When users of slower internet connections upload larger files in the range of 14-20MB the upload seems to timeout and the page refreshes but no success message is given and the PHP script does not seem to complete. From our testing we believe the problem to be browser related, but we are not certain, there is a possiblility it is server related. Please note that we have already changed the upload size and set timeout on the server to unlimited (0) in the .htaccess and [login to view URL] files. We can provide console access for monitoring and troubleshooting. Please bid on the following: * Project must be complete / delivered by Sun Mar 29'th * Need to troubleshoot timeout issue and fix problem fully must work with IE and Firefox. Needs to be a server side solution (i.e. if client browser is timing out need to find a solution to keep connection active) * Would like javascript added to the two upload fields to prevent users from uploading individual files greater than 20MB or any audio + video file combination greater than 20MB