version 6.0 upgrade

I purchased version 5 of Parallels from MacMall with an offer of a free upgrade to version 6.0. MacMall provides a link to a form for the free upgrade. After filling out the form (including the product key) and submitting, I get a message in Firefox (running under OS X stating that the server is unavailable. Submitting the form via Safari leaves me with an infinite hourglass. Either way, I am not able to submit the form.