It seems Mozilla has taken this version off its mirrors: >>> Downloading 'http://releases.mozilla.org/pub/mozilla.org/firefox/releases//3.6.15/linux-i686/en-US/firefox-3.6.15.tar.bz2' --2011-04-07 15:22:10-- http://releases.mozilla.org/pub/mozilla.org/firefox/releases//3.6.15/linux-i686/en-US/firefox-3.6.15.tar.bz2 Auflösen des Hostnamen »releases.mozilla.org«.... 216.165.129.141, 64.50.236.52, 156.56.247.196, ... Verbindungsaufbau zu releases.mozilla.org|216.165.129.141|:80... verbunden. HTTP Anforderung gesendet, warte auf Antwort... 404 Not Found 2011-04-07 15:22:11 FEHLER 404: Not Found. Reproducible: Always add ~www-client/firefox-bin-3.6.16 ~x86 to /etc/portage/package.keywords until it is marked stable.
Then please set a proper GENTOO_MIRRORS in your make.conf. That's what it's for. :)
In what respect is this not proper? # cat /etc/make.conf | grep MIRR GENTOO_MIRRORS="http://gentoo.inode.at/ http://distfiles.gentoo.org"