You don't specify how long it takes before the disconnect, but it sounds as if the browser is timing out before the upload completes. I've never dealt with this, but searching here I did find these nodes that may be of some help:

NPH scripts? (was Re: Browser Timeout)
Browser Timeout
Capturing a Browser Timeout Signal


-THRAK
www.polarlava.com

In reply to Re: uploading large files with CGI.pm by THRAK
in thread uploading large files with CGI.pm by karmakidd2

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