We'll probably have to track this as a BZ if we actually need a code change:
osc build-logs sin-89d70fac-c2b1-11e4-b853-525400b33d1d
Forbidden: "/osapi/v1beta1/redirect/buildLogs/sin-89d70fac-c2b1-11e4-853-525400b33d1d?namespace=sinatra" denied by default