This comes from bug 477844 After adding: sed -i -e "s:python3.2mu:python3.3 python3.2mu:" \ cmake/Modules/FindPython3Interp.cmake || die sed -i -e "s:3.2 3.1 3.0:3.3 3.2 3.1 3.0:" \ cmake/Modules/FindPython3Libs.cmake || die it looks to work against 3.3
python3_3 added in 1.2.1-r1. Actually, the seds weren't even needed.