title: how to set BUILD_MAC_SDK_EXPERIMENTAL=1 on Mac 10.7?
body: <p>I am building Android OS source on Mac 10.7 follow instructions at: <a href="http://source.android.com/source/building.html" rel="nofollow">http://source.android.com/source/building.html</a>. Below are the error code when I try to run <code>lunch full-eng</code></p>
  
  <blockquote>
    <p>BinhNguyens-MacBook:WORKING_DIRECTORY CuongLy$ lunch full-eng
    2012-10-04 14:02:58.544 xcodebuild[645:80b] XcodeColors: load (v10.1)
    2012-10-04 14:02:58.560 xcodebuild[645:80b] XcodeColors:
    pluginDidLoad: build/core/combo/HOST_darwin-x86.mk:62:
    <strong><em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>*</strong> build/core/combo/HOST_darwin-x86.mk:63: * Can not find SDK 10.6 at
    /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.6.sdk
    build/core/combo/HOST_darwin-x86.mk:65: * If you wish to build using
    higher version of SDK,  build/core/combo/HOST_darwin-x86.mk:66: * try
    setting BUILD_MAC_SDK_EXPERIMENTAL=1 before 
    build/core/combo/HOST_darwin-x86.mk:67: * rerunning this command 
    build/core/combo/HOST_darwin-x86.mk:69:
    <strong><em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>**<em>*</em>*</strong> build/core/combo/HOST_darwin-x86.mk:70: <em>*</em> Stop..  Stop.</p>
  </blockquote>
  
  <p>Please tell me how to set BUILD_MAC_SDK_EXPERIMENTAL=1 ?</p>