pastebin.com has updated their website. The 0.5 pastebin no longer works. Upstream has updated to version 0.6 which supports the new public API. It seems to work perfectly on x86 and amd64 (There is a non-zero chance that upstream may come out with a 0.6.1 or 0.7 shortly since I submitted a minor bug about them not supporting all pastebin languages--like the ever-popular ada. This is a very minor issues and should not stop updating to 0.6, but you should check for updates before copying the current 0.5 ebuild to 0.6 and setting up pastebin for mirroring.)
Are you sure that version 0.5 is dead?
Bumped, thanks for reporting.