Unsuccessful attempts to Automate Los Alamos downloads

I've pretty much given up on automating the download of data from the Los Alamos database. It just doesn't seem to lend itself to python's mechanize. The form options are filled in with javascript (which I figured out how to deal with). The big problem is that the download of fasta files occurs through javascript (for some crazy reason) and I just can't seem to find a way to capture the request.