Hi all, I have the Mac OS X 10.6 (Snow Leopard) SDK on my dev system. The presence of this SDK prevents boost 1.36 from building: --snip-- ./tools/jam/src/bin.macosxx86/bjam debug release --toolset=darwin -- architecture=combined --layout=system threading=multi address-model=32 link=shared,static macosx-version=10.4 --prefix=../1_36_0_install -- exec-prefix=../1_36_0_install install boost_1_36_0/tools/build/v2/build/feature.jam:466: in feature.validate- value-string from module feature error: "10.6" is not a known value of feature <macosx-version> error: legal values: "10.5" "10.4" "10.3" "10.2" "10.1" "iphone-2.0" "iphone-1.x" "iphonesim-2.0" boost_1_36_0/tools/build/v2/build/property.jam:276: in validate1 from module property boost_1_36_0/tools/build/v2/build/property.jam:301: in validate from module property boost_1_36_0/tools/build/v2/build/property.jam:310: in property.validate-property-sets from module property boost_1_36_0/tools/build/v2/build/toolset.jam:151: in flags from module toolset boost_1_36_0/tools/build/v2/tools/darwin.jam:227: in init-available- sdk-versions from module darwin boost_1_36_0/tools/build/v2/tools/darwin.jam:178: in darwin.init from module darwin boost_1_36_0/tools/build/v2/build/toolset.jam:38: in toolset.using from module toolset boost_1_36_0/tools/build/v2/build-system.jam:434: in process-explicit- toolset-requests from module build-system boost_1_36_0/tools/build/v2/build-system.jam:513: in load from module build-system boost_1_36_0/tools/build/v2/kernel/modules.jam:281: in import from module modules boost_1_36_0/tools/build/v2/kernel/bootstrap.jam:128: in boost-build from module boost_1_36_0/boost-build.jam:16: in module scope from module --snip-- The workaround was for me to hide the SDK, run configure again, then build. I still can't build successfully, due to an unrelated issue. But I'll post that separately in order to try and keep things clear. Snow Leopard will be here before you know it, so at some point the boost build system should be updated to know about 10.6. For that matter, maybe a new SDK would just generate a warning, not a hard error. Best, -- Allen Cronce