Trying to Dpwnload Trailers in 1080P from Apple Trailers Site?

Hi Guys,

I am trying to download from this site trailers.apple.com and I have the Videodownloader Add on for Mozilla ver 2.1 installed on my computer, now even when the content on the above site is available in 1080P when I download the content and it only shows the 720P format and downloads only that ! Can anyone please help me, whats going wrong in this ? I really like to download trailers in 1080P from this site, any help will be highly appreciated.