[aur-general] iceweasel md5sum problem

Hello, I'm trying to submit the web browser Iceweasel to aur, but I'm having a problem with the md5sum. I wrote the PKGBUILD, used makepkg -g to generate the md5sum and put the output into the PKGBUILD. I made the soruce package with makepkg --source and there was no problem, and doing just makepkg to build the whole package, it is possible to install iceweasel from that package without problems, etc. the only problem is that, when downloading and installing from aur, it gives an error on the integrity check. Could anyone explain me why does it happens? my PKGBUILD it's this one: http://pastebin.com/xZawmpUP Thanks in advance ;)