Installing CMake on MacOSX from the command line

I thought I could just :

curl -O http://www.cmake.org/files/v2.8/cmake-2.8.0-Darwin-universal.dmg

hdiutil attach cmake-2.8.0-Darwin-universal.dmg

cd /Volumes/cmake-2.8.0-Darwin-universal

sudo installer -pkg cmake-2.8.0-Darwin-universal.pkg -target /

Oh well ... it still starts up a message box, where you have to click, yes I want the /usr/bin cmake symlink.

D'oh !