Sounds like your browser is simply timing out..
One trick to get past this is to have you browser autorefresh every 10 seconds or so..
You could have a page displayed saying, "Process request..."
and have the page by refreshed automatically by the browser using a meta tag:http://www.htmlhelp.com/reference/html40/head/meta.html
<META HTTP-EQUIV=Refresh CONTENT="10; URL=http://www.htmlhelp.com/
tells the browser to load http://www.htmlhelp.com/
10 seconds after the current document has finished loading. Not all browsers support this, so authors should provide an alternate means of moving to the new page where necessary. The Refresh header is sometimes used for "splash screens" or when a page has moved, but the technique is not very effective since users may not even be looking at the window that is to be refreshed and since it messes up the user's history on many browsers. Some search engines penalize pages that use a Refresh of a few seconds or less.
Hope this helps,